c. 1300, yolpen, probably echoic variant of yelpen (see yelp). Related: Yawped; yawping. The noun, in reference to speech, is recorded from 1835, now used chiefly in conscious echo of Whitman (1855).
Entries linking to yawp
yelp v.
Old English gielpan (West Saxon), gelpan (Anglian) "to boast, exult," from Proto-Germanic *gel- (source also of Old Saxon galpon, Old Norse gjalpa "to yelp," Old Norse gjalp "boasting," Old High German gelph "outcry"), from PIE root *ghel- (1) "to call, cry out." Meaning "utter a quick, sharp, bark or cry" is 1550s, probably from the noun. Related: Yelped; yelping.