Merriam-Webster Collegiate Dictionary - obsolete

 I. adjective  Etymology: Latin obsoletus, from past participle of obsolescere to grow old, become disused, perhaps from ob- toward + solere to be accustomed  Date: 1579  1.  a. no longer in use or no longer useful an ~ word  b. of a kind or style no longer current ; old-fashioned an ~ technology  2. of a plant or animal part indistinct or imperfect as compared with a corresponding part in related organisms ; vestigial  Synonyms: see old  • ~ly adverb  • ~ness noun  II. transitive verb  (-leted; -leting)  Date: 1640 to make ~