A long time in the rain (3)

I believe the answer is:

era

'a long time' is the definition.
(a long period of time)

'in the rain' is the wordplay.
'in' indicates the answer is hidden within the clue.
'ERA' is hidden in the letters of 'the rain'.

(Other definitions for era that I've seen before include "Distinctive period of time" , "Long period of history" , "Long period of time" , "day" , "Significant time" .)

I've seen this clue in the Evening Standard.

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