Noun. Buttocks, 'arse'. Convoluted Cockney rhyming slang for 'arse'; Ariss, an abbvreviation of Aristotle, rhyming with bottle, and thereafter leading to bottle and glass rhyming with 'arse'. Also aris.
ARRIS
Meaning of ARRIS in English
Slang English vocab. Английский сленговый словарь. 2012