highlight (n.) Look up highlight at Dictionary.com
1650s, originally of paintings, "the brightest part of a subject," from high (adj.) + light (n.). The figurative sense of "outstanding feature or characteristic" is from 1855. Hairdressing sense is 1941. Related: Highlights.
highlight (v.) Look up highlight at Dictionary.com
1861, from highlight (n.). Hairdressing sense is 1942. Related: Highlighted; highlighting.