Balance between September and October (5)

I believe the answer is:

libra

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'balance' is the definition.
(the Scales in the zodiac)

I cannot understand how the rest of the clue works.

(Other definitions for libra that I've seen before include "Someone born between September 23 and October 22" , "Scales star sign" , "Old pound" , "Balance constellation" , "Constellation near Virgo" .)

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

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