Initial insult that can make a chap weep? (3)

I believe the answer is:

sob

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'weep?' is the definition.
(I know that weep can be written as sob)

I can't explain the remainder of the clue.

(Other definitions for sob that I've seen before include "Expression of distress" , "Weep noisily" , "Cry noisily" , "Weep uncontrollably" , "making one gasp" .)

I've seen this clue in the Evening Standard.

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