Crossword Genius

So, coming back in, Les made a deposit (5)

Ross

I believe the answer is:

loess

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'deposit' is the definition.
(sediment deposited by wind)

I can't explain the remainder of the clue.

Can you help me to learn more?

(Other definitions for loess that I've seen before include "geological feature" , "desposit" , "Compacted wind-blown sediment (geology)" , "Silt deposit" , "Wind-deposited silt" .)

I've seen this clue in the Sydney Morning Herald.
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