I suspect it's either 'wank' or 'yank', Harpgirl.
You know how rhyming slang works, right?(Find a two [or more] word phrase that rhymes with the real one, and then drop the rhyme. So 'wank' rhymes with 'J. Arthur Rank', and so you drop the "Rank" part and call it a "J.Arthur").
Blessings,
Barbara