on tail

Related to on tail: oxtail, Whale tail

on (one's) tail

Following or pursuing very close behind someone. The cops are on our tail—we have to lose them in the woods. Why is this guy sitting on my tail when I'm already going over the speed limit?
See also: on, tail
Farlex Dictionary of Idioms.

on someone's tail

Inf. Fig. following someone closely. (See also on someone's heels.) There is a huge truck on my tail. What should I do? Keep on her tail and don't let her out of your sight.
See also: on, tail
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.
See also:
  • on (one's) tail
  • on somebody's tail
  • on someone’s tail
  • on your tail
  • sit on (one's) tail
  • sit on someone's tail
  • be (sitting) on (one's) tail
  • turn tail
  • turn tail, to
  • freeze tail off