dickhead

n. foolish or contemptible person (Slang)

Dick can be used as a pejorative term that refers to an abrasive or inconsiderate person. In this context it can be used interchangeably with "jerk". The variant dickhead can also be used. The term is literal, referring to the individual as a penis. This term comes from the fact that the behavior the person is said to be exhibiting is negative behavior often associated with the male sex.
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Noun
1. insulting terms of address for people who are stupid or irritating or ridiculous
(synonym) asshole, bastard, cocksucker, shit, mother fucker, motherfucker, prick, whoreson, son of a bitch, SOB
(hypernym) unpleasant person, disagreeable person
(classification) obscenity, vulgarism, dirty word

n. คนโง่ (คำสแลงและคำต้องห้าม), ไอ้โง่ (syn. idiot) slang. ปัญญาอ่อน, โง่