1 definition by The Onion-Mangetout-Raddish

The act of performing manual sex (fingering), underwater. If parties involved are truly disgusting, and unaware of health hazards to themselves and others, possibly in a public place, like at the pool. Also known as Sub-Aqua Manual Sex (or SAMS to veterans of the Underwater-Erotic world.) Any person who has performed this feat eight or more times is known as "An Octopus" and often revered as somewhat of a disgusting legend.
Lad 1: Dude! I'm off to do some fish fingering down at the Lido.
Lad 2: Wow really? How many times is this now?
Lad 1: This'll be my 8th.
Lad 2: Oh my god man! You're gonna be an octopus!
Lad 1: Yeah but last time her hidden wreck was barnacle encrusted and covered in seaweed...
Both: *shudders*
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