To have shown fear in checked pants (9)

I believe the answer is:

chickened

'to have shown fear' is the definition.

'in checked pants' is the wordplay.
'pants' indicates an anagram (UK informal term for 'nonsense' or 'rubbish').
'in'+'checked'='inchecked'
'inchecked' with letters rearranged gives 'CHICKENED'.

I've seen this clue in The Guardian.

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