pessimist Definition

pessimism
noun

1. The tendency to emphasize the gloomiest aspects of anything, and to expect the worst to happen.
2. The belief that this is the worst of all possible worlds, and that evil is triumphing over good. Compare optimism.

Derivative: pessimist

Someone who has a sombre gloomy nature.
Thesaurus: cynic, defeatist, melancholic, doomsayer, worryguts slang), worrywart (US slang), killjoy, wet blanket (slang), worrier, complainer; Antonym: optimist.

Someone who follows the doctrine of pessimism.

Derivative: pessimistic
adj

Having a gloomy nature and outlook
Thesaurus: cynical, defeatist, fatalistic, gloomy, morose, depressed, despondent, dismal, resigned; Antonym: optimistic.

Derivative: pessimistically
adverb

Etymology: 18c: from Latin pessimus worst + -ism.