| tvrdýhardAdjective | Adjective |
| tvůjyourPronoun | Pronoun |
| tweettweetNoun | Noun |
| tweetovatto tweetVerb | Verb |
| tyyouPronoun | Pronoun |
| týdenweekNoun | Noun |
| týdenníweeklyAdjective | Adjective |
| týdněweeklyAdverb | Adverb |
| tygrtigerNoun | Noun |
| tykatuse informal addressVerb | Verb |
| týmteamNoun | Noun |
| typtypeNoun | Noun |
| typickytypicallyAdverb | Adverb |
| typickýtypicalAdjective | Adjective |
| uat, near, next toPreposition | Preposition |
| ubytovacíaccommodationAdjective | Adjective |
| ubytováníaccommodationNoun | Noun |
| ubytovnahostel or dormitoryNoun | Noun |
| účastparticipationNoun | Noun |
| účastníkparticipantNoun | Noun |
| účastnit separticipateVerb | Verb |
| učebnaclassroomNoun | Noun |
| učebnicetextbookNoun | Noun |
| učenílearningNoun | Noun |
| účeshairstyleNoun | Noun |
| učesat secomb one's hairVerb | Verb |
| účetbill, receipt, or accountNoun | Noun |
| účetníaccountantNoun | Noun |
| účetnictvíaccountingNoun | Noun |
| učilištěvocational schoolNoun | Noun |
| učitteachVerb | Verb |
| učit selearn; studyVerb | Verb |
| učitelteacherNoun | Noun |
| učitelkafemale teacherNoun | Noun |
| účtenkareceiptNoun | Noun |
| účtovatcharge; keep accountsVerb | Verb |
| údajněallegedly, reportedlyAdverb | Adverb |
| událosteventNoun | Noun |
| udělatdo; makeVerb | Verb |
| údolívalleyNoun | Noun |
| ugrilovatgrillVerb | Verb |
| uhlícoalNoun | Noun |
| uchoearNoun | Noun |
| ujetleave; drive awayVerb | Verb |
| ukázatshowVerb | Verb |
| ukázkasampleNoun | Noun |
| ukazovatshowVerb | Verb |
| ukládatsave; storeVerb | Verb |
| úklidcleaningNoun | Noun |
| ukliditclean up; tidyVerb | Verb |
| uklidnit secalm downVerb | Verb |
| uklízečcleanerNoun | Noun |
| uklízečkafemale cleanerNoun | Noun |
| uklízetclean; tidyVerb | Verb |
| úkoltask or assignmentNoun | Noun |
| ukončitend; terminateVerb | Verb |
| UkrajinaukrajinaUkraineNoun | Noun |
| UkrajinecukrajinecUkrainian manNoun | Noun |
| UkrajinkaukrajinkaUkrainian womanNoun | Noun |
| ukrajinskyin UkrainianAdverb | Adverb |
| ukrajinštinaUkrainian languageNoun | Noun |
| ukráststealVerb | Verb |
| uletětfly awayVerb | Verb |
| ulicestreetNoun | Noun |
| uložitsave; storeVerb | Verb |
| ultrazvukultrasoundNoun | Noun |
| umělecartistNoun | Noun |
| uměleckýartisticAdjective | Adjective |
| umělkyněfemale artistNoun | Noun |
| umělýartificialAdjective | Adjective |
| uměníartNoun | Noun |
| umětknow how; be able toVerb | Verb |
| úmrtídeathNoun | Noun |
| umřítdieVerb | Verb |
| umýtwashVerb | Verb |
| umýt sewash oneselfVerb | Verb |
| umyvadlowash basinNoun | Noun |
| unavenětiredly, in a tired wayAdverb | Adverb |
| unavenýtiredAdjective | Adjective |
| unieunionNoun | Noun |
| uniformauniformNoun | Noun |
| univerzálníuniversalAdjective | Adjective |
| univerzitauniversityNoun | Noun |
| univerzitníuniversityAdjective | Adjective |
| únorFebruaryNoun | Noun |
| únorovýFebruaryAdjective | Adjective |
| upéctbake; roastVerb | Verb |
| úplněabsolutely, fully, completelyAdverb | Adverb |
| uprostředin the middleAdverb | Adverb |
| upřímněhonestly, sincerelyAdverb | Adverb |
| upřímnou soustrastmy sincere condolencesPhrase | Phrase |
| upřímnýhonestAdjective | Adjective |
| úrazinjuryNoun | Noun |
| úrazovýaccidentAdjective | Adjective |
| určitědefinitely, certainlyAdverb | Adverb |
| určitýcertainAdjective | Adjective |
| úroveňlevelNoun | Noun |
| úřadofficeNoun | Noun |
| úřad prácelabour officeWord combination | Word combination |
| úřad sociálního zabezpečenísocial security officeWord combination | Word combination |