eh, ni-, -an
‘head’ to be hit against something vertical.
This refers to hitting the head against a wall, or door, or anything fairly solid and perpendicular to a horizontal plane.
My head was hit against the wall by him.
His head is so hard, this [person's head] should certainly be hit against [something].
He is so hard-headed, he needs to have some sense knocked into him. ["Hard-headed" in English is idiomatic for "stubborn".]