old boy old boy /oʊld bɔɪ/

noun

1. () A familiar term of address for a man  ( old man , old boy )
   a familiar term of address for a man
     The old boy reminisced about his time spent at the prestigious boarding school.
   The old boy reminisced about his time spent at the prestigious boarding school.
   
2. () A vivacious elderly man  ( old boy )
   a vivacious elderly man
    The lively old boy regaled the youngsters with tales from his youth.
   The lively old boy regaled the youngsters with tales from his youth.
   
   
3. A former male pupil of a school  ( old boy )
   a former male pupil of a school