incident
noun
a single distinct event
a public disturbance
“the police investigated an incident at the bus station”
adjective
falling or striking of light rays on something
“incident light”
(sometimes followed by `to') minor or casual or subordinate in significance or nature or occurring as a chance concomitant or consequence
“incidental expenses”
“the road will bring other incidental advantages”
Synonymsincidental
Source: WordNet 3.1, Princeton University