have a bone on

have a bone on

vulgar slang To have an erection. I hope that pretty girl couldn't tell I had a bone on—how embarrassing!
See also: bone, have, on
Farlex Dictionary of Idioms.

have a bone on

tv. to have an erection. (see also bone at boner. Usually objectionable.) Look, friend, you can’t do anything with me till you have a bone on. Get it up or get out. I got other customers waiting.
See also: bone, have, on
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions
See also:
  • bone out
  • bone orchard
  • head bone
  • headbone
  • doesn't have a (certain kind of) bone in (one's) body
  • unkind
  • crazy bone
  • bone dry
  • be bone idle
  • out of joint