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Synonyms for Accessory (same or very similar meaning)

WordNet sense 1 (someone who helps another person commit a crime):

WordNet sense 2 (clothing that is worn or carried, but not part of your main clothing):
accouterment, accoutrement

WordNet sense 3 (a supplementary component that improves capability):
add-on, appurtenance, supplement

WordNet sense 4 (furnishing added support):
adjunct, adjuvant, ancillary, appurtenant, auxiliary, subsidiary

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