Drink can start you ruminating (3)

I believe the answer is:

rum

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'drink' is the definition.
(rum is a kind of drink)

I cannot understand how the remainder of the clue works.

(Other definitions for rum that I've seen before include "Peculiar like sailor's drink (3)" , "Queer" , "Odd, like sailor's drink" , "Odd spirit from sugar cane" , "Odd sort of spirit used in grog" .)

I've seen this clue in the Evening Standard.

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