I. noun
1.
Synonyms: appendage , adjunct, appendix, appurtenance
Related Word: accompaniment, concomitant; accretion, addition, increment
2.
Synonyms: confederate , abettor, accomplice, coconspirator, conspirator
Antonyms: principal
II. adjective
Synonyms: auxiliary , adjuvant, ancillary, appurtenant, collateral, contributory, subservient, subsidiary
Related Word: secondary, subordinate, tributary; coincident, concomitant, concurrent; adventitious, incidental
Contrasted words: constitutional, ingrained, inherent, intrinsic; cardinal, fundamental, vital; essential, indispensable, necessary
Antonyms: constituent, integral