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4.2 Affixes

Specific group of roots can be called affixes. These roots are mostly used with some other roots in composites. However, they can form words also alone, just by adding an ending. This case is not so common as using them in composites and not all theoretically possible forms of using affixes as roots can be found in a real text.
Affixes can be classified into two groups: affixoids (more like a classical root) and true affixes.
The difference between real suffixes and classical roots together with suffixoids is following – when two roots are put together to form a composite, the first root modifies (is a determiner) the meaning of the second (main) root:
dormo|ĉambroroom for sleepingĉambro room is modified by dormito sleep (o after the root dorm is inserted for better pronunciation – see chapter 4.3)
In the case of suffixes, the determination is done in opposite direction:
dorm|egito sleep deeplydormito sleep is modified by the word egabig.
The distinction between Esperanto prefixes and roots is not so obvious. The prefixes are always determining the following root. The result of such a determination can be a modification:
dis|irito go in different direction – the verb irigo is modified by prefix dis.
Or a totally different meaning:
mal|bonabad, the meaning of the word bonagood is negated by the prefix mal.
Another difference is that at least about some true suffixes (, eg, et and um), it is possible to say that they do not have inherent category and are transparent according to the category of the stem they are assigned to.
The distinction between classical roots and true affixes is not clear and depends mostly on a tradition. Different theories put the frontier between roots (and affixoids) and true affixes in a different point. PAG uses following distinction: bo, eks, ge, mal and pra are called true prefixes and , eg, et, um, nj and ĉj are called true suffixes.
For my application, the division between classical roots, affixoids and affixes is not important. It will be driven mostly by practical needs – ffixes are more often used in word building then the rest of roots, so it is good to spend more time with them. A mistake made in rules for an affixoid would produce more errors when analyzing a real text, than a mistake made in rules for an ordinary root.
I will put apart suffixes (aĉ, eg, et and um), because their transparency to the inherent category of the stem and because of different direction of modification of the meaning in composites. I will make no distinction between prefixoids and prefixes.
There are two purposes of this chapter. The first purpose is to prepare direct background for the implementation (prefixes pra and bo, suffixes io, ujo, etc). The second purpose is to show how flexible is the Esperanto word building, to show that it is hard to say that something is impossible. For this reason, the paragraph “Used as a root:” is added. Therefore some important affixes are described in separate chapter, to some is devoted only few lines.

4.2.1 True suffixes

4.2.1.1 Aĉ

The suffix gives to the stem shading of contempt or disgrace, detestation.
ĉevalohorse ĉevalaĉonag
domohouse domaĉohove
hundodog hundaĉocur
parolispeak parolaĉitittle-tattle, twaddle
See also mis- in chapter 4.2.3.5.

Used as a root:
aĉauseless, ugly, aĉaĵ(ar)ojunk, lumber, aĉigidisgust, make something terrible, aĉulougly fellow, aĉularomob, rabble

4.2.1.2 Eg

The suffix eg augments or strengthens the idea shown by the root.
urbotown urbegobig town, city
domohouse domegobig house, mansion
varmahot varmegavery hot, boiling hot
necesanecessary necesegaabsolutely necessary
trevery treegextremely
ridilaugh ridegicachinnate, guffaw

Used as a root:
egaenormous

4.2.1.3 Et

The suffix et is used to form diminutives.
urbotown urbetosmall town
domohouse dometobig house, cottage
varmahot varmetowarm
This suffix can be also used with the names of persons (or family members) to make intimate forms (see also suffixes ĉj, nj: 4.2.2.5)
PaŭloPaul PaŭletoPaul, my bonnie
patrofather patretodad

Used as a root:
etatiny, etulosmall child, etulinosmall girl, etaĵosmall thing, etigito diminish

4.2.1.4 Um

The suffix um has not defined meaning. It just somehow modifies the meaning of the root. The meaning of the resulting word is hard to decode from the knowledge of the root – the only definite thing is that, they have something in common.
ventowind ventumito ventilate
koloneck kolumocollar
akvowater akvumito water, to irrigate, to sprinkle water on
plenafull plenumito fulfill
Used as a root:
umodoohickey, umito do something (If you can not find the right word)

4.2.2 Suffixoids

4.2.2.1 Igi

Verbs created by the suffix ig mean: “to cause, to do something, to be in the state of the stem”. Intransitive verbs are changed into transitive. Verbs with this suffix are often told to be in factitive voice. The suffix ig is very often.
blankawhite blankigito make something white, whitewash
dormisleep dormigiput to sleep
If the suffix is followed by the noun ending the result is the name of the action (pura – clean, purigi – to clean, purigo – cleaning). If the suffix is followed by an adjective ending the result is adjective with meaning doing, able to do or relating to something. (purigapurifying, able to clean, cleaning).
The verb igi means to cause.

4.2.2.2 Iĝi

Verbs created by the suffix mean: “to become, to turn into”. Transitive verbs are changed into intransitive. Verbs with this suffix are often told to be in mediopassive voice. The suffix is also very often.
ruĝared ruĝiĝito become red
naskito born naskiĝito be born
It is possible to form add noun ending (name of the action). Adjectival and adverbial endings are possible, but latter not very often.
The verb iĝi means to become.

4.2.2.3 Ado

The suffix ad emphasizes the process. With the noun ending, it means the name of the action, with the verbal ending, it means repetition or long lasting of the process. For verbal roots, it has the same meaning as adding simple noun ending.
martelohammer marteladohammering, marteladiuse hammer often
irigo ir(ad)o = the act of going, iradito be going for some time
Used as a root:
adacontinual

4.2.2.4 Eco

Suffix ec means quality. The best English counterpart is a suffix -ness. For adjectival roots, it has the same meaning as adding simple noun ending.
riĉarich riĉ(ec)orichness
konfuzitaconfused konfuzitecoconfusedness

Used as a root:
ecoquality, characteristic, ecein a characteristic way, ecahaving the character, ecaro = karakterocharacter (sum of qualities)

4.2.2.5 Ĉj, Nj

The suffixes ĉj (for males) and nj (for females) make from the root an intimate form. The root can be shortened – the suffix is attached after one of the first five letters.
JohannoJack JoĉjoJack
JohanaJoan JonjoJoanie
patrofather paĉjodad, panjomum
filoson fiĉjolittle son, finjolittle daughter
fratobrother fraĉjolittle brother, franjolittle sister
amikofriend amiĉjodear friend (he), aminjodear friend (she)

These suffixes are now not very often used (except few words like paĉjo, panjo) and are very often replaced by suffix et (see 4.2.1.3) or by national intimate forms (Johnny, Dick, Saŝa).

4.2.2.6 Other suffixoids

Aĵo
The suffix aĵo forms a concrete, perceivable manifestation of the root.
novanew novaĵonew thing, novelty
fotografito take photographs fotografaĵophotography
Used as a root:
aĵoa think
Ano
The suffix ano forms a member, participant, resident.
kluboclub klubanomember of the club
Budho Buddha budhanoBuddhist (see also isto)
Used as a root:
anoa member of a club, society, anito be a member, anigito make somebody a member of something, aniĝito become a member, anecomembership, aniĝiloapplication form, etc.
Aro
The suffix aro adds to the root the meaning of a collection.
arbotree arbaroforest
homoman homaromankind (≠ aro da homojgroup of people)
Used as a root:
arogroup, ara (adj.), are (adv.) – in groups, grandarein big groups, arito be in group, ariĝito group oneself, arigito group somebody
Ejo
The suffix ejo means place where something is performed or where something is kept, a building, etc.
lernito learn lernejoplace for learning, school
preĝito pray preĝejoa church, musk, etc (kirko = church)
ministrominister ministrejodepartment
Used as a root:
ejoplace
Ero
The suffix ero means an element of the thing expressed by the root. Not nominal stems are automatically nominalized (as if suffix aĵo were added).
panobread paneroa crumb of a bread
neĝosnow neĝerosnow flake
kudrito sew kudreroa stitch
Used as a root:
eroelement, grain, eretosmall element, granderacoarse-grained, diseriĝito disintegrate (intransitive), diserigito cause to disintegrate
Estro
The boss of the thing expressed by the stem.
ŝipoship ŝipestrocaptain
urbotown urbestromayor
The boss of some group of people can be expressed also by prefixing the root ĉefochief.
Used as a root:
estroboss, estrito direct, estraroboard of directors
Ido
The suffix id forms an offspring, young creature, etc.
hundodog hundidopuppy
plantoplant plantidosmall plant
latinaLatin latinida lingvojlanguages with the Latin origin
Used as a root:
idooffspring, idetosmall young, idaroall descendants
Ilo
The suffix il means a tool for doing whatever is expressed by the preceding root.
tranĉito cut tranĉilotool for cutting, a knife
komputito compute computiloa computer
buterobutter buterito butter buteriloknife for buttering
linioline liniito line liniilo ruler
Used as a root:
iloinstrument, ilaroset of tools, ilujobox for tools, ilejoworkshop
Ino
The suffix in means a female.
patrofather patrinomother
bovocow bovinoshe-cow
Esperanto is a sexist language. Most of roots with meaning of human beings are of the male sex. Today more and more of them are considered neutral. Especially professional titles are neutral. The male equivalent of this suffix is a prefix vir-, it can be added to roots which sex is neutral.
katocat virkatinotomcat
Ingo
The suffix ingo has a meaning of a holder for the thing described by root.
kandelocandle kandelingocandle-holder
Used as a root:
ingoholder, mostly sheath, ingi = eningigto put into the holder, sheath, malingi = elingigito put out of the holder, unsheathe
Ismo
The suffix ismo has a meaning of a doctrine, movement, system, etc.
Budho budhismo, Markso marksismo
ĵurnalonewspaper ĵurnalismojournalism
Used as a root: ism – movement, doctrine
isto
The suffix isto has a meaning of an individual professionally occupied with something, somebody who is used to do something. The suffix can be also used as equivalent for two suffixes ist|ano. This is not used if the ismo is added to the member of the movement, etc. (krist|ano – Christian kristanismo – Christianity).
laborito work laboristoa worker
lingvolanguage lingvistolinguist
Budho budhisto, Markso marksisto
Ujo
The suffix ujo has three meanings:
1) A container or box for something. This is the main meaning.
paperopaperpaperujo = paperkestobox for paper
salosalt salujosaltcellar, saltshaker
2) A tree having fruit or flowers specified by stem. This meaning of the suffix is rather archaic, today it is replaced by forming a composite with arbotree or arbetosmall tree.
pomoapple pomujo = pomarboapple-tree
3) A country for the nationality expressed by the stem. See chapter 4.3.4 Names of countries.
ItaloItalian Italujo = ItalioItaly
When the suffix ujo is used as a root, it has the first meaning – a box or container.
Ebla
The meaning of suffix ebla is “suitable for being done.
legito read legeblareadable
farito do farebla possible to be done
Used as a root:
eblapossible, possible to be done, eblemaybe, eblo = eblecopossibility, eblaĵopossible thing, possibility, ebligienable, ebliĝito become possible, maleblaimpossible
Ema
The meaning of the suffix ema is “to have tendency or inclination to do the thing described by the stem.
laborito work laboremaindustrious
dormito sleep dormemasleepy
Used as a root:
emainclining, emoinclination, emiincline, emiĝito become inclining, emigito cause that something is inclining
Enda
The meaning of the suffix enda is “it must be done the thing described by the stem
skribito write skribendathat must be written
vidito see videndathat must be seen
Used as a root:
endamandatory, endonecessity, endiit is necessary
Inda
The suffix inda has meaning “worthy -ing
farito do farindaworth doing
vidito see vidindaworth seeing
Used as a root:
indaworthy, indito be worthy, indigito make something worthy, malindato be unworthy, senidulo – unworthy man

4.2.3 Prefixes

4.2.3.1 Bo

Bo marks relative by marriage. In English, the same thing is done by adding in-law.
bofratobrother-in-law, bofiloson-in-law, bopatrinomother-in-law, bokuzocousin-in-law, bonevograndson-in-law, etc.

The exception is a word for child coming from the previous marriage(s) of one of the spouse – it is marked by prefixing duon[31].

Bo can be also used in following words:
boparencorelatives by marriage
bofamilianomember of the family by marriage
boedziĝito marry with the wife of one’s dead brother (used by Zamenhof in the translation of Bible)
boamikojocular way to call friend of one’s spouse

There is no distinction between relatives got by one marriage and relatives got by two marriages: mia bofrato is brother of my spouse or husband of the sister of my spouse.

If bo is together with prefix ge (see 4.2.3.2), bo stands before ge[32]: bogefratojbrothers-in-law and sisters-in-law.

The prefix as a root:
boulo = boparencorelative-in-law, boeco = boparentecothe type relation between two relatives-in-law, boabeing of the in-law type of relation

4.2.3.2 Ge

Ge marks both sexes. This prefix is used before roots of male beings or roots that are neutral from the point of the sex.
geknabojboys and girls, gejunulojyoung people, youth, geinstruistojteachers of the both sexes
For neutral words, the prefix is very often not necessary. Words like lernantoj (pupils) or doktoroj (doctors.) are good enough for describing beings of both sexes and the prefix ge is used only for stressing the fact that people in the group are of both sexes.
The plural after the word with this preposition is common, but not necessary: geedzo – spouse, gepatro – parent.
The meaning of the prefix can be slightly different, depending on context:
1) A pair (e.g. of husband and wife): gepatroj – mother and father, parents, geonkloj – uncle and aunt, geedzoj – husband and wife, geamantoj – lovers.
2) Members of the same type, but both sexes of a family: gefiloj – sons and daughters of the same family.
3) The whole family: geurbestroj – the family of the mayor

Prefix ge is also used with things that do not have sex. In that case, it means that the things are related with both sexes: gelernandocoeducation, gelernejocoeducational school. However, this usage is quite rare.

As root:
geohe and she, pair, geamixed, etc. (gea lernejo = gelernejocoeducational school), geiĝi = pariĝimake pairs from oneself, geigi = parigito pair

4.2.3.3 Mal

Prefix mal denotes total opposite to the stem.
malbelaugly, malvarmacold, malgrandasmall, malrapidaslow, malamihate, malaperidisappear, malamikoenemy, malantaŭbehind.
Prefix mal is very often used. In the beginnings of the language, it was nearly the only way of finding an opposite for most of the words. Even very common words (malgrandasmall, malfermiopen, malnovaold, etc) had to be expressed using this prefix. Today, some synonyms to the mal- words exist, some of them are used more and some of them less often: fini = malkomencifinish, frida = malvarmacold, breva = mallongashort, eta = malgrandasmall, dura = malmolahard, cis = maltrans - on this side (transacross), olda = malnovaold, etc.

As a root:
malo opposite (noun), malaopposite (adj.) maleopposite (adv.), oppositely, malindaundesirable, unwelcome, etc.

4.2.3.4 Pra

Prefix pra has following meanings:
1) With names of relatives, one generation older or younger: praavo – great-grandfather, pranepo – great-grandson, praonklo – great-uncle. The prefix pra can be even repeated: prapraavo – great-great-grandfather. For the father of the father and for the son of the son are words avo and nepoprapatro and prafilo belong to the second category.
2) Very distant in time (mostly in the past – ancient or primeval): praarbaro – primeval forest, pratempo – primeval ages, prahistorio – prehistory, prabesto – primeval animal, prahomo – primeval human, prapatro – founder of the family, of the kin or nation, prafilo – descendants after many generations.

As a root:
praeprimevally, praaprimeval, praeco – “primevalness”, praulo = primeval ancestor, forefather

4.2.3.5 Other prefixes

Eks
Eks marks something former. It is mostly used in front of the word with the meaning of some profession or function.
eksprezidantoex-president, eksposedantoformer owner, eksdirektoroformer director, eksurbestroformer mayor, eksedzoformer husband, eksedziĝito divorce oneself, eksmodaout of the fashion
Eks used as a root: eksigito force somebody to abdicate, eksiĝiabdicate, leave a club, eksaquondam, abdicated, eks! – Eks pri la reĝo!Away with the king!
Dis
Prefix dis means separation in different directions, scattering.
irito go disirito go in different directions
vojoway disvojiĝoroad-fork
Ek
Prefix ek means the beginning or ephemerality.
irito go ekirito start to go, to set out
kriito shout ekkriito shout out
Ek can be also used alone as an interjection: Ek!Let’s start!, Ek al li!MLet’s catch him. Or as a verb: eki = komenciĝistart (intransitive), begin, ekigistart (transitive)
For
Prefix for means removing, disappearing, distance, spoiling.
irito go foririto leave
dormito sleep fordormito spoil time by sleeping
Mis
Prefix mis expresses an error or incorrectness. In contrary to the suffix aĉ, this prefix is used in objective stating.
kalkulicalculate miskalkulimiscalculate
tradukitranslate mistradukimistranslate
kompreniunderstand miskomprenimisunderstand
Mis used as a root:
misaincorrect, erroneous, misito err
Re
Prefix re means returning or repetition.
venito come revenito come back, to return (intransitive)
metito place remetito put back, to return (transitive)
legiread relegiread again
Re can be used alone in reeagain, reenback, rea – adjective from ree or reen.

4.2.4 Unofficial affixes

There are also many unofficial affixes. I list only the most often ones:
-ivacapable of doing something
produktiproduct produktivaproductive
-eskasimilar to, or in the manner of
japanoa Japanese japaneskaJapanesque
-ala – is used to derive adjectives from nouns derived from adjectives
varmahot varmoheat varmalathermal
-oidaresembling; having the appearance of; related to, mostly technical
antropohuman antropoidoanthropoid
-ozafull of
poropore porozaporous
-izato apply something (thing or method) to an object
salosalt salizi ionadd salt to something
retro-in the opposite direction
irigo retroirito go in opposite direction

There is also large amount of affixes used in some special field – in chemistry (-ozaferoza – ferous, -ikasulfika – sulfuric, etc), in botany, medicine (-ozosklerozo – sclerosis, -itodermatito – dermatitis) and so on.

4.2.5 Pseudoaffixes

Some of the unofficial affixes are partly so called pseudoaffixes. They are mostly affixes in the languages the Esperanto vocabulary comes from.
Many of Esperanto roots are composites in the language they come from. Therefore, some roots start or finish with the same sequence of characters. These sequences look as an affix. However, the rest of such a word is very often not an Esperanto word. On the other hand, sometime new words are created connecting these sequences with Esperanto roots. These elements are called pseudoaffixes (pseŭdoafiksoj).
Typical example is a pseudosuffix logio: ornitologioornithology, zoologiozoology, etc. However, there are also words metodologiomethodology (metodomethod), antropologioanthropology (antropohuman). And there are also purely Esperanto words: esperantologioscience about Esperanto, birdologioornithology, formologiomorphology, etc. In these words is a suffix ologio.
Another pseudosuffixes are iko (poeto – poet poetiko – poetics, stilisto – stylist stilistiko – stylistics), acio, icio (delegacio – delegation, operacio – operation, pozicio – position, etc) and many others.
There are also pseudoprefixes: aŭto (autobiografio – autobiography, aŭtomobilo – car, aŭtonomio – autonomy, aŭtokratoautocrat), anti (antikristo, antisemito), (eŭfemismo – euphemism, eŭgeniko – eugenics) and others.
Most of these words are treated as separate roots in Esperanto. Some of them can be considered as unofficial affixes (ologio, iko). In contrary to classical affixes, these cannot be used systematically (sometimes is ok ologio, sometimes iko).

[31] See chapter 3.7.2.6 - Fractions.
[32] This is opinion of the PAG (§417). PMEG (bo) is not so strict, it states that the order of the bo and ge does not matter, and that it is only a habit to put ge first.