(vb) to grab, squeeze and/or pull the testicles, either through the clothes or by opening the fly, to cause more or less severe pain. English. knacker knackers

Sometimes as a joke, often as torture, occasionally so that the victim will be so preoccupied with his pain that he desists from some antisocial behaviour.
He was being too aggressive, so I knackerised him. That gave him something to think about.

There's (name)! It's his birthday: grab him and knackerise him! Make his day!
by frankieco January 16, 2012
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