when your testicle (knacker) gets really sweaty (clammy) and sticks to your leg.
Bollocks, i've got clammy knacker again!

This clammy knacker is pissing me off!

I wish i didn't get clammy knacker all the time!

I've recently entered "Clammy Knacker" into the urban dictionary!
by Mr Curt August 6, 2007
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