ancillary /an-silˈə-ri or anˈsi-lə-ri/

1. Auxiliary
2. Supplementary
3. Subsidiary
4. Subordinate
5. (of computer equipment) additional in any way, not a necessary part of the computing process
6. Subserving
7. Ministering

An ancillary thing

• self-improvement
• self-incompatibility
• self-incompatible
• self-induced
• self-inductance
• self-induction
• self-inductive
• self-indulgence
• self-indulgences
• self-indulgent
• self-indulgently
• self-infection
• self-infections
• self-inflicted
• selfing
• selfings
• self-inject
• self-injected
• self-injecting
• self-injection
• self-injections
• self-injects
• self-insurance
• self-interest
• self-interested