unheard-of
adjective
-ˌäv\
Definition of unheard-of
: previously unknown especially : unprecedented moving at unheard-of speeds
Synonyms & Antonyms for unheard-of
Synonyms
fresh, new, novel, original, strange, unaccustomed, unfamiliar, unknown, unprecedented
Antonyms
familiar, hackneyed, old, time-honored, tired, warmed-over
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More Definitions for unheard-of
unheard-of
adjective
English Language Learners Definition of unheard-of
: not known to have existed or happened before : very unusual
See the full definition for unheard-of in the English Language Learners Dictionary
unheard-of
adjectiveKids Definition of unheard-of
: not known before an unheard-of invention
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