"even matter," 1809, from earlier sense of "a flipping of a coin to arrive at a decision" (c. 1700), from verbal phrase, from toss (v.) + up (adv.).
it's a toss-up whether he will win or lose
Tory
tosh
toss
tosser
tosspot
toss-up
tostada
tot
total
totalitarian
totalitarianism