holler (v.) Look up holler at Dictionary.com
1690s, American English, variant of hollo (1540s) "to shout," especially "to call to the hounds in hunting," related to hello. Compare colloquial yeller for yellow, etc. As a style of singing (originally Southern U.S.), first recorded 1936. Related: Hollered; hollering. As a noun, from 1896, earlier hollar (1825).