adjunct
1. [ noun ] something added to another thing but not an essential part of it
Related terms: inessential
2. [ adjective ] relating to something that is added but is not essential
Synonyms: ancillary adjuvant appurtenant auxiliary subsidiary accessory
Examples:

"an ancillary pump" "an adjuvant discipline to forms of mysticism" "The mind and emotions are auxilliary to each other"

Related terms: supportive
3. [ adjective ] of or relating to a person who is subordinate to another
Synonyms: assistant
Related terms: subordinate
4. [ noun ] (grammar,linguistics) a construction that is part of a sentence but not essential to its meaning and can be omitted without making the sentence ungrammatical
Related terms: construction parenthetical
5. [ noun ] a person who is an assistant or subordinate to another
Related terms: associate
Similar spelling:   adjunctive
  adjunction
  adducent
  adducing