Beheaded it would be even more venomous (4)

I believe the answer is:

wasp

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'it would be even more venomous' is the definition.
The definition suggests a singular noun which matches the answer.

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(Other definitions for wasp that I've seen before include "Striped stinger" , "Insect often irritating in summer" , "colonist" , "Insect; thin (waist)" , "Influential American" .)

I've seen this clue in The Globe and Mail.

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