
Arse
Informal Slang
Arse is very informal and often considered rude; use in casual settings only.

Oops, I've just texted my boss 'Arse over tit', that was inappropriate.
Not for Formality
Avoid 'arse' in formal writing or speaking, instead use 'buttocks' or 'rear end'.

In the medical report, he wrote 'buttocks' instead of 'arse'.
Humorous Insult
Used jokingly among friends, but can offend if the relationship isn't close.

My mates laughed when I said, 'I fell on my arse'.
Compare with
BacksideBootyBumButtockPosteriorTush
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