What is "mole hunt"?

Thank you
BW, you have submitted a great many questions recently with short phrases and no context. It is almost impossible many times to give you a good answer without knowing how it was used. PLEASE give us more to work with, and we can give you a better response.
GG is right. All we can say from what you've given is that a mole hunt is a hunt for moles, an attempt to find moles.

Do you know what a mole is? Do you know what a hunt is? Just put the two together! Emotion: smile

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It might depend on the context.

One possibility:
"Mole" could be a term for "spy," and "mole hunt" could be a search for a spy. Moles dig tunnels underground where they can hide, and I think the original idea was that a spy could "burrow" into an organization.
 BarbaraPA's reply was promoted to an answer.
 CalifJim's reply was promoted to an answer.
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