Of uncertain origin, probably risen out of a British dialect (OED finds candidate words in Herefordshire, Gloucestershire, southern Cheshire, and Sheffield). "The formation seems to be onomatopœic, expressive of the notion of throwing down roughly and untidily" [OED]. 
- To confuse; to fluster; to flabbergast.
2011 January 22, “Man Utd 5 - 0 Birmingham”, in BBC:
- With United's movement flummoxing the visitors, Berbatov saw his low shot saved well by Ben Foster on his first return to Old Trafford.
- See also Thesaurus:confuse