unheard of
/ʌnˈhɜrdˌʌv/
adjective
- So unusual or extreme that it has never happened or been known before.
- The company offered an unheard-of salary to attract the best talent.
- In those days, a woman becoming a doctor was almost unheard-of.
- It is unheard-of for a student to skip three grades in one year.
Synonyms