He is just having a J. Arthur in his room.
J. Arthur
idiom Vulgar
Cockney rhyming slang · East London
wank
Origin
via J. Arthur Rank
The teenager was embarrassed when his mother walked in while he was having a J. Arthur.
The protagonist retreated to the privacy of his quarters, choosing to have a J. Arthur rather than face the social pressures of the evening.
Last updated June 6, 2026