Q: why the huge difference in spelling? A: first, consider this other word: https://www.etymonline.com/word/barbarian >from PIE root *barbar- echoic of unintelligible speech of foreigners (compare Sanskrit barbara- "stammering," also "non-Aryan," Latin balbus "stammering," Czech blblati "to stammer"). the story that I've head is that "foreigners sound like they're just saying 'bar bar bar' all the time".