'Unheard-of' definitions:

Definition of 'unheard-of'

adjective

Previously unknown; "a first novel by an unheard of writer"; "developments on an unheard-of scale"

Definition of 'Unheard-of'

From: GCIDE

Unheard-of \Un*heard"-of\, a. New; unprecedented; unparalleled. --Swift. [1913 Webster]

Synonyms of 'unheard-of'

From: Moby Thesaurus

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