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English definition of “un-”


prefix uk   /ʌn-/ us  
used to add the meaning 'not', 'lacking', or 'the opposite of' before adjectives, adverbs, verbs, and nouns: unrealistic unhappily unscrew unfairnessYes, no and notLacking thingsScarce, inadequate and not enoughEssential or necessary
(Definition of un- prefix from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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