1) Bear 2) Crapehanger 3) Defeatist 4) Naysayer 5) Negativist 6) Nonbeliever 1) Cynical one 2) Dark horse 3) Defeatist 4) Detractor 5) Disparager 6) Doom merchant 7) Doomsayer 8) Doubter 9) Fatalist 10) French word used in English 11) He views with alarm 12) Misanthropist 13) One expects the worst 14) Quitter 15) Sceptic 16) Skeptic 
• (a.) Alt. of Pessimistic • (n.) One who advocates the doctrine of pessimism; -- opposed to optimist. • (n.) One who looks on the dark side of things.
Pes'si·mist noun [ Latin pessimus worst: confer French pessimiste .] 1. (Metaph.) One who advocates the doctrine of pessimism; -- opposed to optimist . 2. One who looks on the dark side of things. 
[n] - a person who expects the worst
pessimist, pessimists 1. Someone who always expects the worst to happen. 2. A person who habitually sees or anticipates the worst or is disposed to be gloomy. Pessimists see the world as excessively cruel in many aspects.
noun a person who expects the worst
a person who expects the worst