Monarch leaves grave to weep (3)

I believe the answer is:

sob

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'weep' is the definition.
(I know that sob is a type of weep)

I cannot understand how the remainder of the clue works.

(Other definitions for sob that I've seen before include "Insulting expression, initially" , "Cry noisily" , "Weep heavily, wail" , "making one gasp" , "Weep audibly" .)

I've seen this clue in The Sun.

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