Crossword Genius

Annoyed with a deserter failing to commence duty? (5)

Ross

I believe the answer is:

ratty

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'annoyed' is the definition.
(thesaurus)

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(Other definitions for ratty that I've seen before include "Short" , "Characteristic of pest" , "Irritable (colloq.)" , "Moley's friend" , "Wretched" .)

I've seen this clue in the Evening Standard.
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