Definition - confuse; perplex; fluster
Bumfuzzle has been in use since the middle of the 19th century, although it appears to be slouching towards obsolescence. We’re not certain where it comes from, although it is possible that it is descended from dumfound (which had variants such as dumfoozle and bumfoozle). If you want to claim that bumfuzzle is based on some meaning of bum compounded with fuzzle (an archaic word meaning “to intoxicate”) you certainly can. You'd almost certainly be wrong, but at least you’d have an entertaining etymology.
When he got to the stairs, another, a sister of the first kissist and huggist, did the thing over again. He was bumfuzzled, but supposed the matter would soon be explained; and it was. The girls had mistaken him for their uncle.
— The Weekly Caucasian (Lexington, MO), 6 Sept. 1873