not of prime or central importance; "nonessential to the integral meanings of poetry"- Pubs.MLA
(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"; "extra duties incidental to the job"; "labor problems incidental to a rapid expansion"; "confusion incidental to a quick change"
become more intense; "The debate intensified"; "His dislike for raw fish only deepened in Japan"
make more intense, stronger, or more marked; "The efforts were intensified", "Her rudeness intensified his dislike for her"; "Pot smokers claim it heightens their awareness"; "This event only deepened my convictions"
make the chemically affected part of (a negative) denser or more opaque in order produce a stronger contrast between light and dark