Meaning of old boy

old boy

Pronunciation: (ōld' boi' for 1, 2 ōld' boi&sec for 3 ōld&sec boi' for 4), [key]
  1. . an adult male, esp. a Southerner. Cf.
  2. a lively elderly man.
  3. an alumnus, esp. of a boys' preparatory or public school.
  4. See
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.