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Synonyms for Arm (same or very similar meaning)

WordNet sense 1 (an administrative division of some larger or more complex organization):
branch, subdivision

WordNet sense 2 (any instrument or instrumentality used in fighting or hunting):
weapon, weapon system

WordNet sense 3 (the part of a garment that is attached at the armhole and that provides a cloth covering for the arm):

WordNet sense 4 (any projection that is thought to resemble a human arm):

WordNet sense 5 (prepare oneself for a military confrontation):
fortify, gird, build up

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