Translation guide
The English word 'arsehole' can refer to the anus or be used as a vulgar insult for a contemptible person. This guide covers natural Japanese equivalents for both meanings, with emphasis on common usage and register.
Referring to the anus in a crude or vulgar way.
Literally 'ass hole'. This is the most direct and common vulgar equivalent. Used in casual, rough speech.
That guy says his arsehole itches.
Medical/formal term for 'anus'. Not vulgar, but can be used in crude contexts if intended humorously or bluntly.
My arsehole hurts.
Calling someone a despicable, annoying, or worthless person in a very offensive way.
Strong vulgar insult meaning 'shit bastard' or 'asshole'. Combines 'kuso' (shit) and 'yarō' (bastard). Very common in angry, rough speech.
That arsehole lied again.
Literally 'dregs' or 'scum'. Used as an insult for a worthless person. Less directly equivalent to 'arsehole' but conveys similar contempt.
Literally 'shit-drip' or 'shithead'. A vulgar insult similar to 'arsehole'. Somewhat old-fashioned or dramatic.
While 'ケツの穴' literally means 'arsehole', it is not commonly used as an insult for a person in Japanese. Using it that way would sound unnatural. Instead, use insults like 'クソ野郎' or 'カス' to convey the same contempt.
He is an arsehole. (unnatural)
All options for the insult meaning are extremely rude and should only be used in very casual, angry, or rough situations. In polite company, avoid these entirely or use milder terms like '嫌な奴' (いやなやつ, unpleasant guy).
You're an arsehole.
You arsehole!