on (one's) case

on (one's) case

Constantly or frequently nagging, harassing, or annoying someone. My boss has been on my case all week to get that report done. I'm sorry for getting on your case about it, but I need an answer soon.
See also: case, on
Farlex Dictionary of Idioms.

*on someone's case

 and *on someone's back
Inf. harassing someone about a personal problem; annoying someone. (*Typically: be ~; get ~; keep ~.) I'll get on Tom's case about being late so much. I'm sorry, I won't get on your case anymore.
See also: case, on
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

on (someone's) case

Persistently nagging or urging someone to do something.
See also: case, on
American Heritage® Dictionary of the English Language, Fifth Edition.
See also:
  • on case
  • be on (one's) case
  • be on somebody's case
  • be on someone's case
  • off (one's) case
  • off case
  • on back
  • be on somebody's back
  • on someone's back
  • be on (one's) back