A peasant’s muddy feet (9)

I believe the answer is:

anapaests

'feet' is the definition.
(anapaest is a kind of foot)

'a peasant's muddy' is the wordplay.
'muddy' indicates anagramming the letters (letters get muddied or confused).
'peasants' anagrammed gives 'napaests'.
'a'+'napaests'='ANAPAESTS'

I've seen this clue in The Sunday Times.

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