| о {letter} | :: The sixteenth letter of the Ukrainian Cyrillic alphabet |
| о {noun} | :: The Cyrillic letter О, о |
| о {noun} | :: The Roman letter O, o |
| о {interj} | :: oh |
| о {prep} | :: (+ prepositional case) about, of, on |
| о {prep} | :: (+ accusative case) against, upon |
| обговорення {noun} | :: discussion, talk |
| Об'єднані Арабські Емірати {prop} | :: Об'єднані Арабські Емірати (country) |
| об'єднання {noun} | :: association (organization of people based on common goals, objectives) |
| об'єднання {noun} | :: union |
| об'єкт {noun} | :: object |
| об'єм {noun} | :: volume, capacity, bulk |
| обід {noun} | :: dinner, lunch |
| обід {noun} | :: lunchtime |
| обід {noun} | :: noon |
| обід {noun} | :: rim, felly |
| обіцяти {vt} | :: to promise, to pledge |
| область {noun} | :: province, region, territory |
| область {noun} | :: sphere (of influence etc.) |
| обличчя {noun} | :: face |
| обличчя {noun} | :: character |
| обов'язковий {adj} | :: compulsory, mandatory |
| обов'язок {noun} | :: duty, responsibility |
| обожнювати {vt} | :: to adore, to love, to worship |
| обожнювати {vt} | :: to apotheosize |
| оборона {noun} | :: defense |
| образ {noun} | :: image (graphical representation) |
| образ {noun} | :: icon (sacred image) |
| обрус {noun} | :: tablecloth |
| обсерваторія {noun} | :: observatory |
| обставина {noun} | :: circumstance, condition, case |
| обсяг {noun} | :: volume, extent, scope, size |
| овес {noun} | :: oats |
| овід {noun} | :: botfly, oestrus |
| овоч {noun} | :: vegetable |
| Огайо {prop} | :: Огайо (state) |
| Огайо {prop} | :: Огайо (river) |
| огірок {noun} | :: cucumber (plant) |
| огляд {noun} | :: examination |
| огляд {noun} | :: inspection, review |
| огляд {noun} | :: survey, review |
| огляд {noun} | :: viewing |
| оглядати {v} | :: to inspect, to examine |
| оглядати {v} | :: to consider, to evaluate |
| оглядати {v} | :: to see |
| оглядини {noun} | :: the traditional rite of inspection of a bride or groom's household by the other party's family |
| оглядини {noun} | :: inspection |
| оглянути {v} | :: to inspect, to examine |
| оглянути {v} | :: to consider, to evaluate |
| одежа {noun} | :: clothing, clothes |
| оден {num} | :: alternative form of оди́н |
| Одеса {prop} | :: Одеса (city) |
| один {num} | :: one (1) |
| одинадцятий {adj} | :: eleventh |
| одинадцять {num} | :: eleven (11) |
| однина {noun} | :: singular |
| одноголосний {adj} | :: unanimous |
| однокласниця {noun} | :: classmate (female) |
| одружуватися {v} | :: to get married, to marry |
| одуд {noun} | :: hoopoe |
| одяг {noun} | :: clothes, clothing, garments |
| одягти {vt} | :: to dress, to clothe |
| ожина {noun} | :: blackberry (plant) |
| ожина {noun} | :: blackberry (fruit) |
| озеро {noun} | :: lake (body of water) |
| озерце {noun} | :: a small lake |
| озимий {adj} | :: autumn, before winter |
| озимі {noun} | :: winter cereals, winter crops |
| ознака {noun} | :: sign |
| ознака {noun} | :: indication |
| ознака {noun} | :: token, evidence |
| ознака {noun} | :: feature, characteristic |
| океан {noun} | :: ocean (one of the five large bodies of water) |
| око {noun} | :: eye |
| око {noun} | :: A unit of weight, approximately 1.2 kg |
| око {noun} | :: A measure for alcoholic beverages, approximately 1-1.5 liters |
| окріп {noun} | :: boiling water |
| окріп {noun} | :: dill (Anethum graveolens) |
| Оксана {prop} | :: given name |
| оладка {noun} | :: alternative form of оладок |
| оладок {noun} | :: thick pancake |
| Олександр {prop} | :: given name |
| Олена {prop} | :: given name |
| олень {noun} | :: deer |
| олива {noun} | :: olive (tree and fruit) |
| олива {noun} | :: lampante olive oil |
| олива {noun} | :: motor oil |
| Олин {adj} | :: Olya's |
| олівець {noun} | :: pencil |
| олія {noun} | :: liquid fat |
| олія {noun} | :: cooking oil |
| олія {noun} | :: oil paint |
| олія {noun} | :: grease (for technical uses) |
| олово {noun} | :: tin (element) |
| Ольга {prop} | :: given name |
| оман {noun} | :: inula, elecampane (Inula spp., especially Inula helenium) |
| онук {noun} | :: grandson |
| онука {noun} | :: granddaughter |
| опариш {noun} | :: maggot (dipterous insect's larva that eats decomposing flesh) |
| опера {noun} | :: opera |
| операція {noun} | :: operation |
| описати {vt} | :: to describe |
| описувати {vt} | :: to describe |
| опозиція {noun} | :: opposition |
| оранжевий {adj} | :: orange (color) |
| оргазм {noun} | :: orgasm |
| організація {noun} | :: organization |
| організувати {v} | :: to organise |
| орден {noun} | :: decoration, order |
| орден {noun} | :: order |
| орден {noun} | :: order |
| орел {noun} | :: eagle |
| оригінальність {noun} | :: originality |
| орудний {adj} | :: instrumental |
| оса {noun} | :: wasp |
| освіта {noun} | :: education |
| освітологія {noun} | :: educology |
| осел {noun} | :: donkey, ass |
| оселедець {noun} | :: herring |
| оселедець {noun} | :: topknot (hairstyle favored by Ukrainian Cossacks) |
| осердя {noun} | :: core |
| осердя {noun} | :: lead |
| осердя {noun} | :: pericardium |
| осінній {adj} | :: autumn, autumnal |
| осінь {noun} | :: autumn, fall |
| Осло {prop} | :: Осло (capital city) |
| основа {noun} | :: basis, base, foundation |
| особа {noun} | :: person, human being, personage, individual |
| особа {noun} | :: person |
| особистий {adj} | :: personal (relating to a particular person) |
| особливість {noun} | :: peculiarity |
| особовий {adj} | :: personal |
| останній {adj} | :: last, final |
| останній {adj} | :: latest, most recent |
| острів {noun} | :: island |
| отава {noun} | :: aftergrass, aftermath; grass that comes up after mowing |
| отець {noun} | :: father |
| отримати {vt} | :: to receive |
| отруїти {v} | :: to poison |
| отруйний {adj} | :: poisonous, toxic |
| отрута {noun} | :: poison |
| охорона {noun} | :: protection, security |
| охоронець {noun} | :: guard, guardian, watcher |
| оцей {determiner} | :: alternative form of цей |
| оцет {noun} | :: vinegar |
| оцінка {noun} | :: assessment, mark (school) |
| очерет {noun} | :: reed (genus Phragmites) |
| очерет {noun} | :: reeds |
| очиці {noun} | :: diminutive of о́чі |
| очиці {noun} | :: endearing form of о́чі |
| очікувати {vt} | :: to wait |
| очко {noun} | :: endearing diminutive of о́ко |
| очко {noun} | :: small window, peephole |
| очко {noun} | :: knitting ring |
| очко {noun} | :: small hole |
| очко {noun} | :: spot, pip |
| очко {noun} | :: eye |
| очко {noun} | :: small stone in a ring |
| очко {noun} | :: point |
| очко {noun} | :: blackjack |
| очко {noun} | :: face (the raised part of a piece of type) |