The rich, bottom to top, are trim (5)

I believe the answer is:

shave

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'are trim' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for shave that I've seen before include "Tonsure" , "Knock off" , "Barber" , "Remove facial hair" , "Remove unwanted hair" .)

I've seen this clue in The Hindu.

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