WordNet sense 1 (an arithmetic operation performed on floating-point numbers):

floating-point operation

WordNet sense 2 (someone who is unsuccessful):

dud, washout

WordNet sense 3 (a complete failure):

bust, fizzle

WordNet sense 4 (fail utterly; collapse):

founder, fall through, fall flat

WordNet sense 5 (the act of throwing yourself down):

collapse

WordNet sense 6 (exactly):

right