unheard-of

1. 1.

   previously unknown

   “a first novel by an unheard of writer”

   “developments on an unheard-of scale”

   Similarunknown

Questions about unheard-of

What does unheard-of mean?

unheard-of means "previously unknown".

How many syllables are in unheard-of?

unheard-of has 4 syllables and divides as un-he-ar-d-of under the regular spelling rules. It is not in the CMU Pronouncing Dictionary, so that comes from how the word is written rather than from a recorded pronunciation, and no stress or phonetic transcription is claimed for it.

Is unheard-of a common word?

unheard-of is banded "Uncommon" — turns up in careful writing rather than conversation. The band comes from how often the word appears in a large corpus of everyday English, not from an editor's impression.