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of a discarded or outmoded type; out of date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, esp., 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.

to make obsolete by replacing with something newer or better; antiquate

Automation has obsoleted many factory workers.

adjective

contemporary , current , in vogue , modern , new , present , up-to-date

adjective

anachronistic , ancient , antediluvian , antiquated , antique , archaic , bygone , dated , dead , dead and gone , dinosaur , discarded , disused , done for * , dusty , extinct , fossil , gone , had it , has-been , horse and buggy , kaput * , moldy * , moth-eaten * , old , old-fashioned , old-hat , old-school , out * , outmoded , out-of-date , out-of-fashion , outworn , pass , stale , superannuated , superseded , timeworn , unfashionablenotes:things that are no longer used or needed are obsolete ; things that are becoming obsolete are obsolescent , obsolescent , out , outdated , passe , rudimentary , unfashionable

verb

outdate , superannuate