- 1incidental (to something) happening in connection with something else, but not as important as it, or not intended The discovery was incidental to their main research. incidental music (= music used with a play or a movie to give atmosphere) You may be able to get help with incidental expenses (= small costs that you get in connection with something).
- 2incidental to something (technology) happening as a natural result of something These risks are incidental to the work of a firefighter.
Check pronunciation: incidental