incidental

Etymology

From incident + -al.

adj

1. Loosely associated; of limited relevance except indirectly; only accidentally related.
   That character, though colorful, is incidental to the overall plot.
   incidental evidence
2. Existing tangentially, being a byproduct, a tangent, or a likely consequence.
   Injuries are incidental to contact sports: they're going to happen.
3. Occurring by chance.
4. (physics, of radiation) Entering or approaching, prior to reflection (more frequently incident).

noun

1. Minor items, not further defined. Incidental expense.
   She's costing us a lot in incidentals.
2. Something that is incidental.