pessimist

noun

1. Someone who habitually expects the worst outcome; one who looks on the dark side of things.

   “I will not marry a pessimist, a born loser, a fellow who has no fight in him.”

   “We are becoming as a nation, as a world, indeed, atom-conscious. Many of us are already afflicted with atomphobia, though so far it has manifested itself only in a mirage of autoaeromotive discs and a war of words between chronic optimists and empirical pessimists concerning civilization’s probable future.”