1510s, Scottish interjection, a natural expression of amazement. "This old interjection had a new popularity in the early 1900s and again during the 1960s and later" [DAS].
"overwhelm with delight or amazement," 1924, American English slang, from wow (interj.). Related: Wowed; wowing. Used as a noun meaning "unqualified success" since 1920.
(also wowee-kazowee or wowie-kazowie) An exclamation of pleasure, wonder, admiration, surprise, etc •This old interjection had a new popularity in the early 1900s and again during the 1960s and later: Wow, what a nice voice you have!/ Oh, wow, far out!/ Hey, wow!/ I have a PhD in communications from UCLA. Well, wowee-kazowee!/ Big rock-'n'-roll concerts are often as much about wowiekazowie production values, video, neon, fireworks, suggestively costumed young men and women, as music (entry form 1513+, variants 1990s+)
nounTo impress someone powerfully and favorably; KNOCK someone DEAD, lay them in the aisles: wondering whether he'll make a fraternity and whether or not he'll wow the girls/ all self-proclaimed poets who, to wow an audience, utter some resonant line (1920s+ Show business)
Related Terms[echoic of a bark or howl of approval]
An intrusive wavering sound from a record player, usually caused by uneven running of the turntable
[1930s+ Electronics; echoic of a howl or yowl]