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?
on someone's tail
Inf. Fig. following someone closely. (See also someone's heels">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.
on your tail
COMMON If someone is on your tail, they are following you closely or are chasing you and trying to catch you. He entered the finishing lap of the race with Piper right on his tail. He heard the wail of police sirens, loud and close by. They must be on his tail at last.
on somebody’s ˈtail
(informal) (of the police, a spy, etc.) following behind somebody very closely: I had the feeling there was someone on my tail.on someone’s tail
mod. following someone closely. There is a huge truck on my tail. What should I do?