"stupid person," 1967, originally U.S. student slang, perhaps from earlier meaning "penis" (1964), itself probably an alteration of dick. Related: Dorky; dorkiness.
To do the sex act with or to; ruin or confound as if by violating sexually; fuck, screw: I said to myself, ''I dorked him,'' but the ball just kept floating like it was floating on air (1970s+)