also whiz-bang, whizz-bang, 1915, originally a soldier's name for a type of German artillery shell in World War I, so called by the Allied troops in reference to its characteristic sound. From whizz + bang (v.).
"make or move with a humming, hissing sound," 1540s, of imitative origin. Meaning "to urinate" is from 1929. Related: Whizzed; whizzing. The noun is recorded from 1610s. Whizzer "something extraordinary" is from 1888.
1540s, "to strike hard with a loud blow," an imitative formation, or else from a Scandinavian source akin to Old Norse banga "to pound, hammer" also of echoic origin. Slang meaning "have sexual intercourse with" attested by 1937. As an adverb, "suddenly, abruptly," by 1828, probably from the notion of "with a sudden or violent sound." Related: Banged; banging. Banging (adj.) in the slang sense of "large, great, surpassing in size" is attested by 1864. Bang-up (adj.) "excellent, first-rate, in fine style" (1810) probably is shortened from a phrase such as bang up to the mark.
Others are reading
<a href="https://www.etymonline.com/word/whizbang">Etymology of whizbang by etymonline</a>
Harper, D. (n.d.). Etymology of whizbang. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/whizbang