one off the wrist 

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.

one off the wrist by Jimi p September 10, 2008

one off the wrist 

a term for wanking

i was sitting in my bedroom watching countdown and decided to have one off the wrist over carol vorderman.

one off the wrist by bake bean head December 5, 2003

one off the wrist 

To wank using the hand.

He gave himself one off the wrist.

one off the wrist by Edna Sweetlove September 27, 2006

having one off the wrist 

Another way of saying I'm going to masterbate

I put a lock on your door so your mum can't catch you having one off the wrist

having one off the wrist by Wanglerz July 23, 2017

Swift one off the wrist 

To masturbate

That girl looks so hot i think i'll just pop to the toilet and have a swift one off the wrist

Swift one off the wrist by saddlesniffer September 26, 2014