Onychotillomania is a compulsive neurosis in which a person picks constantly at the nails or tries to tear them off.

Why are we constantly picking on Iran and ignoring the threat to peace from Israel?

Teams constantly picked on Raymond because they knew he could be beat.

Now Christopher paced the terrace, picking at his teeth and constantly watching the road that led across the hill.

Barry was expelled from school at age 15 for attacking a group of bullies who constantly picked on and bullied his best friend Terry Sullivan.

Conrad and Vernon: Two bullies who constantly pick on Ned.

A big bully, loud-mouth, and in reality a coward, who constantly picks on Cavin.

He constantly picked on Josh and the other kids with his gang of associates.

She constantly picks on Ii-chan due to his personality.

He turned out to be the type to constantly pick a fight, is what I gather.