Crowding around ensign too curiously (10)

I believe the answer is:

congestion

'crowding' is the definition.
(I know that congestion is a type of crowding)

'around ensign too curiously' is the wordplay.
'around' becomes 'c' (abbreviation for 'circa').
'curiously' indicates anagramming the letters.
'ensign'+'too'='ensigntoo'
'ensigntoo' is an anagram of 'ongestion'.
'c'+'ongestion'='CONGESTION'

(Another definition for congestion that I've seen is " Overcrowding".)

I've seen this clue in The Daily Express.

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