Merriam-Webster's Collegiate® Dictionary, 11th Edition
ALONE
I. adjective
Etymology: Middle English, from al all + one one
Date: 13th century
separated from others ; isolated , exclusive of anyone or anything else ; only ,
3. considered without reference to any other , incomparable , unique , aloneness noun Synonyms: see: alone
II. adverb
Date: 13th century
solely , exclusively , without aid or support