What is the meaning of alone?

adjective

• Isolated from others.
  • usage: "could be alone in a crowded room"; "was alone with her thoughts"; "I want to be alone"
• Lacking companions or companionship.
  • usage: "he was alone when we met him"; "she is alone much of the time"; "the lone skier on the mountain"; "a lonely fisherman stood on a tuft of gravel"; "a lonely soul"; "a solitary traveler"
  • synonyms: lone, lonely, solitary
• Exclusive of anyone or anything else.
  • usage: "she alone believed him"; "cannot live by bread alone"; "I'll have this car and this car only"
  • synonyms: only
• Radically distinctive and without equal.
  • usage: "he is alone in the field of microbiology"; "this theory is altogether alone in its penetration of the problem"; "Bach was unique in his handling of counterpoint"; "craftsmen whose skill is unequaled"; "unparalleled athletic ability"; "a breakdown of law unparalleled in our history"
  • synonyms: unique, unequaled, unequalled, unparalleled

adverb

• Without any others being included or involved.
  • usage: "was entirely to blame"; "a school devoted entirely to the needs of problem children"; "he works for Mr. Smith exclusively"; "did it solely for money"; "the burden of proof rests on the prosecution alone"; "a privilege granted only to him"
  • synonyms: entirely, exclusively, solely, only
• Without anybody else or anything else.
  • usage: "the child stayed home alone"; "the pillar stood alone, supporting nothing"; "he flew solo"
  • synonyms: solo, unaccompanied