Crossword Genius

Rodent entering that is angry (5)

Ross

I believe the answer is:

irate

'angry' is the definition.
(irate can mean angry or annoyed)

'rodent entering that is' is the wordplay.
'rodent' becomes 'rat' (rat is a kind of rodent).
'entering' indicates putting letters inside.
'that is' becomes 'ie' (abbreviation for id est, 'that is' in Latin).
'rat' inserted into 'ie' is 'IRATE'.

(Other definitions for irate that I've seen before include "Extremely cross" , "Cross, irritated" , "Angry and incensed" , "Annoyed, irritated" , "Ticked off" .)

I've seen this clue in The Times.
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