Merriam-Webster's Collegiate® Dictionary, 11th Edition
SOLITARY
I. adjective
Etymology: Middle English, solitarie, from Anglo-French, from Latin solitarius, from solitas aloneness, from solus alone
Date: 14th century
1. being, living, or going alone or without companions, saddened by isolation, unfrequented , desolate ,
3. taken, passed, or performed without companions , keeping a prisoner apart from others , being at once single and isolated ,
5. occurring singly and not as part of a group or cluster , not gregarious, colonial, social, or compound , see: alone solitarily adverb solitariness noun
II. noun (plural -taries)
Date: 15th century
one who lives or seeks to live a solitary life ; recluse , solitary confinement in prison