What is Obsolete?

Obsolete definition and meaning on Dictionary terms:
no longer in general use; fallen into disuse: an obsolete expression.
of a discarded or outmoded type; out of date: an obsolete battleship.
(of a linguistic form) no longer in use, especially, out of use for at least the past century.Compare archaic.
effaced by wearing down or away.
Biology. imperfectly developed or rudimentary in comparison with the corresponding character in other individuals, as of the opposite sex or of a related species.

verb (used with object), ob