Definition of "dickhead"

...down, down, sinking down faster than she's so far moved, the dick head exploding up into all that wet, warm slime...

1970, Clarence Major, All-night Visitors, page 71

I don't want them Special Forces guys left out there when some dickhead is afraid to go get them.

1965, Robin Moore, The Green Berets, page 242

...they have been exchanging insults in writing: "dickhead," "dillweed," "fuzzbutt," "dorkwad," "asswipe," and so forth.

1996, Timothy Jay, What to Do When Your Students Talk Dirty, page 207

"Watch it, dickhead!" "Hey, Stan, that's my shirt you just dropped in the snow!"

1979, E.M. Corder, The Deer Hunter, page 69