adjective

1. no longer in use or practice; discarded
2. no longer in fashion; out-of-date; passé
3. Biol. rudimentary or poorly developed as compared with its counterpart in other individuals of a related species, the opposite sex, etc.; vestigial: said of an organ, etc.

Etymology: L obsoletus, pp. of obsolescere, to go out of use < ob- (see ob-) + *-solescere (< exolescere, to grow out of use < ex-, ex- + ? alescere, to increase: see adolescent)

transitive verb obsoleted -·let′ed, obsoleting -·let′·ing