Pronunciation: (un-hûrd'uv", -ov", -uv), [key]
1. that was never heard of; unknown: an unheard-of artist.
2. such as was never known before; unprecedented: an unheard-of salary.
3. shocking or outrageous: unheard-of conduct.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.