Crossword Genius

Recruits dropping water into river (8)

Ross

I believe the answer is:

trainees

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'recruits dropping' is the definition.
I can't judge whether this definition defines the answer.

'water into river' is the wordplay.
'water' becomes 'rain' (rain is a kind of water).
'into' is an insertion indicator.
'river' becomes 'tees' (River Tees).
'rain' inserted inside 'tees' is 'TRAINEES'.

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