Abolish my less unmanly practices (5)

I believe the answer is:

annul

I'm a little stuck... Click here to teach me more about this clue!

'abolish' is the definition.
(I've seen this in another clue)

I cannot understand how the remainder of the clue works.

(Other definitions for annul that I've seen before include "Render invalid" , "Nullify" , "scratch" , "Declare void" , "Cancel or render void" .)

I've seen this clue in the Sydney Morning Herald.

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