Act of flowing in (6)

I believe the answer is:

influx

'act of flowing in' is the definition.
(I've seen this before)

This is all the clue.

(Other definitions for influx that I've seen before include "Arrival en masse" , "Arrival in large numbers" , "Act of flowing in" , "Sudden arrival in numbers" , "Large visitation" .)

I've seen this clue in The Guardian and the Evening Standard.

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