Circulating damp polluted air in strange plant-holder (9)

I believe the answer is:

terrarium

'plant-holder' is the definition.
(plant-filled container)

'circulating damp polluted air in strange' is the wordplay.
'circulating' is a reversal indicator.
'damp' becomes 'ret' (ret can mean to dampen or moisten).
'polluted' indicates an anagram.
'in' means one lot of letters goes inside another.
'strange' becomes 'rum' (synonyms).
'ret' backwards is 'ter'.
'air' anagrammed gives 'ari'.
'ari' inserted within 'rum' is 'rarium'.
'ter'+'rarium'='TERRARIUM'

I've seen this clue in The Times.

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