A suffix is glued to the end of a stem, and unlike a prefix it usually changes the part of speech: a noun becomes an adjective, a verb becomes a noun. Vinur "friend" plus -legur gives the adjective vinalegur "friendly"; kenna "to teach" plus -ari gives the noun kennari "teacher." Knowing the productive suffixes lets you do two things at once — decode an unfamiliar long word by recognising its ending, and build the word you need from a stem you already have. This page is a reference catalogue that deepens the broader Derivation page (which introduces these suffixes one by one) by laying them out by resulting word class with their English analogues; for the prefixes (ó-, endur-, van-…) see the companion Prefix Catalogue, and for the fine detail of turning verbs into nouns see Nominalisation. The headline: two of these suffixes are exact one-to-one matches for English (-laus = "-less", -legur ≈ "-ly/-like"), so they are productively decodable, while -leiki and -skapur are the two great abstract-noun formers ("-ness/-ity/-ship").
The catalogue at a glance
| Suffix | Makes a… | From | Meaning | English analogue | Example |
|---|---|---|---|---|---|
| -legur | adjective | noun / verb | "having the quality of" | -ly, -ish, -al, -like | vinalegur "friendly" |
| -laus | adjective | noun | "without, lacking" | -less | atvinnulaus "unemployed" |
| -samur | adjective | noun | "inclined to, full of" | -some, -ful | friðsamur "peaceable" |
| -ugur | adjective | noun | "covered in, having" | -y | grösugur "grassy" |
| -leiki / -leikur | noun (abstract) | adjective | quality, "-ness" | -ness, -ity | veikleiki "weakness" |
| -skapur | noun (abstract/collective) | noun / adjective | state, "-ship" | -ship, -hood, -dom | vinskapur "friendship" |
| -ari | noun (agent) | verb | "one who does" | -er, -or | kennari "teacher" |
| -ing / -un | noun (deverbal) | verb | action / result | -ing, -tion | könnun "survey" |
Adjective-makers
-legur — the great adjective-maker ("-ly / -ish / -like")
-legur is the workhorse adjective suffix, roughly English -ly / -al / -ish / -like: it forms an adjective meaning "having the quality of, characterised by." It is highly productive — attach it to a noun (or verb) and you get a quality adjective. (Sometimes the stem takes a linking -a-: vinur → vinalegur, barn → barnalegur.)
| Base |
| Adjective |
|---|---|---|
| vinur "friend" | vinalegur | friendly |
| barn "child" | barnalegur | childish |
| kona "woman" | kvenlegur | feminine, womanly |
Þjónninn var rosalega vinalegur og stakk upp á réttinum.
The waiter was really friendly and suggested the dish. (vinur 'friend' + -legur → vinalegur 'friendly')
Ekki vera svona barnalegur, þú ert fullorðinn maður.
Don't be so childish, you're a grown man. (barn 'child' + -legur → barnalegur 'childish')
-laus — "-less" (the exact English match)
-laus is the precise counterpart of English -less: it attaches to a noun and says the thing is absent. It is the cleanest one-to-one suffix in the language — if you know the noun, noun + -laus gives you the "-less" adjective. (It is the same word as the adjective laus "loose, free, vacant.")
| Noun |
| Adjective |
|---|---|---|
| von "hope" | vonlaus | hopeless |
| atvinna "employment" | atvinnulaus | unemployed (work-less) |
| heimili "home" | heimilislaus | homeless |
Hann hefur verið atvinnulaus síðan verksmiðjunni var lokað.
He's been unemployed since the factory closed. (atvinna 'work' + -laus → 'without work')
Þetta er gjörsamlega vonlaust, við náum aldrei síðasta strætó.
This is utterly hopeless, we'll never catch the last bus. (von 'hope' + -laus → vonlaus 'hopeless')
-samur — "-some / prone to"
-samur forms adjectives meaning "inclined to, full of, characterised by" — like English -some / -ful. Friður "peace" + -samur → friðsamur "peaceable, given to peace."
| Base |
| Adjective |
|---|---|---|
| friður "peace" | friðsamur | peaceable |
| spara "to save" | sparsamur | thrifty, frugal |
| hjálp "help" | hjálpsamur | helpful |
Nágranni minn er einstaklega hjálpsamur — alltaf til í að rétta hjálparhönd.
My neighbour is exceptionally helpful — always up for lending a hand. (hjálp 'help' + -samur → hjálpsamur 'helpful')
Amma var mjög sparsöm og henti aldrei mat.
Grandma was very thrifty and never threw away food. (spara 'save' + -samur → sparsamur 'thrifty')
-ugur — "-y" (covered in / full of)
-ugur forms adjectives meaning "covered in, having, full of", much like English -y (grass → grassy). It often triggers a vowel change in the stem.
Túnið var grösugt og blautt eftir rigninguna.
The field was grassy and wet after the rain. (gras 'grass' + -ugur → grösugur 'grassy', with u-umlaut a→ö)
Strákurinn kom inn forugur upp fyrir haus.
The boy came in muddy up to his ears. (for 'mud' + -ugur → forugur 'muddy')
Noun-makers
-leiki / -leikur — abstract quality ("-ness / -ity")
-leiki (also -leikur) turns an adjective into an abstract noun naming the quality — the Icelandic -ness / -ity. Veikur "weak" → veikleiki "weakness"; möguleg(ur) "possible" → möguleiki "possibility." A famous lexicalised one is kærleikur "love (charitable, deep love)," from kær "dear."
| Adjective |
| Abstract noun |
|---|---|---|
| veikur "weak" | veikleiki | weakness |
| mögulegur "possible" | möguleiki | possibility |
| kær "dear" | kærleikur | (deep) love, charity |
Það er enginn möguleiki á því að klára þetta í dag.
There's no possibility of finishing this today. (mögulegur 'possible' → möguleiki 'possibility')
Hver og einn hefur sína styrkleika og veikleika.
Everyone has their own strengths and weaknesses. (veikur 'weak' → veikleiki 'weakness')
-skapur — state / collective ("-ship / -hood / -dom")
-skapur forms abstract or collective nouns — a state, condition, or body of something — like English -ship / -hood / -dom. Vinur "friend" → vinskapur "friendship"; kunningi "acquaintance" → kunningsskapur "acquaintanceship." All -skapur nouns are masculine.
| Base |
| Noun |
|---|---|---|
| vinur "friend" | vinskapur | friendship |
| kunningi "acquaintance" | kunningsskapur | acquaintanceship |
| félag "association" | félagsskapur | company, fellowship |
Vinskapur þeirra hefur enst í þrjátíu ár.
Their friendship has lasted thirty years. (vinur 'friend' → vinskapur 'friendship')
Takk fyrir góðan félagsskap í kvöld.
Thanks for the good company tonight. (félag 'association' → félagsskapur 'company/fellowship')
-ari and -ing/-un — agents and actions
For completeness, two deverbal formers introduced on the Derivation page. -ari makes the agent (the doer) from a verb — English -er/-or: kenna "teach" → kennari "teacher," leika "act/play" → leikari "actor." -ing and -un make action/result nouns from verbs — English -ing/-tion: kanna "investigate" → könnun "survey," kenna "teach/posit" → kenning "theory."
Leikarinn fékk standandi lófaklapp í lok sýningarinnar.
The actor got a standing ovation at the end of the show. (leika 'act' + -ari → leikari 'actor')
Ný könnun sýnir að flestir styðja breytinguna.
A new survey shows that most people support the change. (kanna 'investigate' + -un → könnun 'survey')
English vs Icelandic: which suffixes are "free"
The practical question is which of these you can apply on sight. Two are essentially free because they map one-to-one onto English: -laus is -less (take any noun, add -laus), and -legur behaves like -ly/-ish/-like (take a noun, add -legur — vinalegur, eðlilegur). The abstract-noun formers -leiki and -skapur are productive but lexically a bit fixed — you should recognise them everywhere and reach for them, but check the established word rather than coining freely (vinskapur, not *vináttuleiki). The wrinkle English speakers miss is that the derived word is fully Icelandic in shape: it triggers native sound changes (gras → grösugur with u-umlaut), it inflects like any other adjective or noun, and agent -ari attaches to the verb stem (baka → bakari), not a borrowed Latin root the way English -or often does (act → actor). Learn the ending, learn the word class it produces, and long Icelandic words stop being opaque.
Common Mistakes
❌ Hann er án atvinnu maður núna.
Roundabout — use the ready-made -laus adjective: hann er atvinnulaus.
✅ Hann er atvinnulaus núna.
He's unemployed now.
When English would say "-less / without," build the -laus adjective rather than a prepositional phrase. atvinnulaus is one tidy word.
❌ vonalaus
Wrong stem-join — -laus attaches to the bare noun: vonlaus.
✅ vonlaus
hopeless (von 'hope' + -laus)
-laus joins the bare noun: von + laus → vonlaus, not *vonalaus. (Compare -legur, which sometimes does take a linking -a-: vinalegur.)
❌ Þeirra vinaleiki hefur enst í áratugi.
Wrong suffix for 'friendship' — that's the -skapur noun vinskapur, not a -leiki form.
✅ Vinskapur þeirra hefur enst í áratugi.
Their friendship has lasted decades.
"Friendship" is the established -skapur noun vinskapur. Don't coin *vinaleiki — recognise which abstract-noun suffix the language actually uses for a given stem.
❌ Hún er mjög hjálplaus manneskja og hjálpar alltaf til.
Opposite meaning — -laus is '-less': hjálparlaus means 'helpless'. For 'helpful' use -samur: hjálpsöm.
✅ Hún er mjög hjálpsöm manneskja og hjálpar alltaf til.
She's a very helpful person and always pitches in.
Watch the suffix's meaning: -laus makes "-less" (hjálparlaus "helpless"), while -samur makes "-ful / prone to" (hjálpsamur "helpful"). They are near-opposites.
❌ Túnið var grasugt eftir rigninguna.
Missed the umlaut — gras + -ugur triggers a→ö: grösugt.
✅ Túnið var grösugt eftir rigninguna.
The field was grassy after the rain.
The -ugur suffix triggers a native u-umlaut in the stem: gras → grösugur. The derived word takes Icelandic shape, accents and all.
Key Takeaways
- Adjective-makers: -legur ≈ "-ly/-ish/-like" (vinalegur "friendly"); -laus = "-less" (atvinnulaus "unemployed"); -samur = "-some/-ful" (hjálpsamur "helpful"); -ugur = "-y" (grösugur "grassy").
- -laus and -legur are the most decodable — they map one-to-one onto English -less and -ly/-like, so you can build them on sight.
- Noun-makers (abstract): -leiki/-leikur = "-ness/-ity" off adjectives (veikleiki "weakness," möguleiki "possibility"); -skapur = "-ship/-hood" off nouns/adjectives (vinskapur "friendship") — all masculine.
- Deverbal nouns: -ari = agent "-er" off a verb (kennari, leikari); -ing/-un = action "-ing/-tion" (könnun "survey," kenning "theory").
- The derived word is fully Icelandic: it takes native sound changes (gras → grösugur) and inflects normally. Learn the ending → know the word class and meaning.
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Start learning Icelandic→Related Topics
- Derivation: Prefixes and SuffixesB1 — The productive derivational affixes of Icelandic — agent -ari, abstract -ing/-un/-leiki/-skapur, adjective-forming -legur/-laus/-samur, and the prefixes ó- (negation), and- (counter-), endur- (re-), van- (mis-/under-), for-/frum- — with the headline insight that ó- productively negates almost any adjective, doubling your vocabulary.
- Prefix Catalogue: ó-, and-, endur-, van-, sam-B1 — A working catalogue of the productive Icelandic prefixes — ó- (negation: óþarfur 'unnecessary'), and- (counter/against: andstæða 'opposite'), endur- (re-: endurtaka 'repeat'), van- (under/mis-: vanmeta 'underestimate'), sam- (co-/together: samvinna 'cooperation'), for- (pre-/fore-: forseti), mis- (mis-: misskilja 'misunderstand'), gagn- (counter/through: gagnrýni 'criticism') — each mapped onto its English/Latin analogue so you can decode and build words on sight.
- Nominalisation: Making Nouns from Verbs and AdjectivesB2 — How Icelandic builds nouns out of verbs and adjectives. Deverbal nouns in -ing/-un name the action (bygging 'building', skoðun 'examination'); the -andi present participle nominalises as an agent (nemandi 'student', stjórnandi 'director'); and DEADJECTIVAL abstracts in -leiki/-d/-t/-ð name the quality (fegurð 'beauty', hæð 'height', lengd 'length'). The headline insight: deadjectival abstracts systematically trigger i-umlaut (hár→hæð, langur→lengd, breiður→breidd, djúpur→dýpt) — the very same vowel change as the comparative — so the abstract noun and the comparative share a vowel. Build native nouns instead of importing English '-tion' words.
- Agent and Instrument NounsB2 — Two ways Icelandic names the doer of an action: the productive -ari suffix (bakari, kennari, leikari), masculine with a regular plural in -arar, and the -andi type (nemandi, eigandi, stjórnandi), built on the present participle, also masculine but with an IRREGULAR plural in -endur (nemandi → nemendur). Instrument nouns use the same -ari machinery (opnari 'opener', þurrkari 'dryer'). The headline contrast: same gender, two different plurals.
- Icelandic Adjectives: Agreement and Two DeclensionsA2 — The big picture of the Icelandic adjective: it agrees with its noun in gender, number, and case, AND it has two complete declensions — strong (indefinite, gamall maður) and weak (definite, gamli maðurinn) — so a single adjective has dozens of forms, chosen by the definiteness of the whole noun phrase.