Meaning of second banana

sec'ond banan'a

Pronunciation: [key]
— Informal. Informal.
  1. a comic who supports the leading comedian, often as a straight man, esp. in burlesque or vaudeville.
  2. any person who plays a secondary role or serves in a subsidiary capacity. Cf.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.