What does alive mean?
The definition of alive
A*live”, a.
Etym: [OE. on live, AS. on life in life; life being dat. of lif life. See Life, and cf. Live, a.]

1 Having life, in opposition to dead; living; being in a state in which the organs perform their functions; as, an animal or a plant which is alive.
2 In a state of action; in force or operation; unextinguished; unexpired; existent; as, to keep the fire alive; to keep the affections alive.
3 Exhibiting the activity and motion of many living beings; swarming; thronged. The Boyne, for a quarter of a mile, was alive with muskets and green boughs. Macaulay.
4 Sprightly; lively; brisk. Richardson.
5 Having susceptibility; easily impressed; having lively feelings, as opposed to apathy; sensitive. Tremblingly alive to nature’s laws. Falconer.
6 Of all living (by way of emphasis). Northumberland was the proudest man alive. Clarendon.

Note: Used colloquially as an intensive; as, man alive!
Note: Alive always follows the noun which it qualifies.