harm a hair on headharm a hair on (someone's) head
to hurt someone.
He adores the girl - he wouldn't harm a hair on her head.
(often negative)
If he so much as harms a hair on her head, I won't be responsible for my actions.
(redirected from harm a hair on head)
harm a hair on (one's) head
To hurt or injure one in any way. This phrase is often used in the negative. If I find that he harmed a hair on your head, I'll go to his house right now!He wouldn't dare harm a hair on your head—not when I'm around.