Desert? Not a lot of water (4)

I believe the answer is:

drop

This clue is a double definition.

'desert?' is the first definition.
(I've seen this before)

'not a lot of water' is the second definition.
(I've seen this before)

(Other definitions for drop that I've seen before include "Bit of water" , "Small drink" , "Sweet; fall" , "Not a lot of water" , "Fall; abandon" .)

I've seen this clue in The Globe and Mail.

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