It is, indeed, yet another euphemism for masturbation.

As the description suggests, it generally refers to male masturbation.
I spent half the day, at work, in a cubicle in the toilets; fantasizing about rough sex with my boss, while having one off the wrist. Eventually I had to move to another cubicle when the toilet roll ran out.
by Jimi p August 11, 2006
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i was sitting in my bedroom watching countdown and decided to have one off the wrist over carol vorderman.
by bake bean head December 5, 2003
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He gave himself one off the wrist.
by Edna Sweetlove September 27, 2006
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I put a lock on your door so your mum can't catch you having one off the wrist
by Wanglerz July 23, 2017
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That girl looks so hot i think i'll just pop to the toilet and have a swift one off the wrist
by saddlesniffer September 26, 2014
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