Note going backwards and forwards (5)

I believe the answer is:

minim

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'note' is the definition.
(musical note)

I don't understand the remainder of the clue.

(Other definitions for minim that I've seen before include "Two crotchets in one" , "Half-note" , "Beat" , "Short note" , "A note in music, half as long as a semi-breve- it's a palindrome" .)

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