Use One's Head Meaning

(humorous) To headbutt.

Example: 1918, Stephen Leacock, "Back from the Land" in Frenzied Fiction:
  He never—so they agreed—uses his head. He never—I think I have their phrase correct—stops to think.
1957, Joyce Jackson, "Guide to Dating," Toledo Blade, p. 35, 13 March:
  When a girl falls in love, after first using her head to find a suitable mate to fall in love with, it is such a wonderful feeling.
2007, Chris Thornton, "A Belfast Father's Vindication," Time, 23 Jan.:
  Bound by that commitment, he used his head, channeling his rage into a determination to bring the killers to justice.