Span whack is a term used to define someone who needs to be told off. A term used in an engineering factory to tell an apprentice off for doing wrong. Usually to be hit on the knuckles hands by a spanner or other tool.
Or most recently used to describe someone who does not know how to do the job as he has been beaten once to often
I’ll span whack you
Bloody hell Karen’s a right span whack.
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