pick on

pick on  {v.}
1.  {informal}
To make a habit of annoying or bothering (someone); do or say bad things to (someone).
Other boys picked on him until he decided to fight them.
Syn.: PICK AT (3).
2. To single out; choose; select.
He visited a lot of colleges, and finally picked on Stanford.
Categories: bother {informal} {v.}