noun
Slang, derogatory term for the head. Rough and informal; used in casual or vulgar speech.
お前、ド頭ぶつけたのか？
Did you hit your head, you idiot?
あいつのド頭をはたいてやった。
I smacked that guy on his noggin.
Standard, neutral word for head. ド頭 is a slang, derogatory variant.
The prefix ど is an intensifier or vulgarizing element, possibly from ど (emphatic prefix). たま is a slang or dialectal variant of あたま (head). The exact derivation is uncertain.