Synonyms for Adjunct (same or very similar meaning)
WordNet sense 1 (furnishing added support):
accessory, adjuvant, ancillary, appurtenant, auxiliary, subsidiaryWordNet sense 2 (furnishing support or assistance):
supportiveWordNet sense 3 (of or relating to a person who is subordinate to another):
assistantWordNet sense 4 (lower in rank or importance):
low-level, subordinateFrom the ODE community, based on WordNetadd/edit