1, 3. Cynical, pessimistic, sarcastic, satirical imply holding a low opinion of humanity. Cynical suggests a disbelief in the sincerity of human motives: cynical about honesty. Pessimistic implies a more or less habitual disposition to look on the dark side of things, and to believe that the worst will happen: pessimistic as to the future. Sarcastic refers to sneering or making cutting jibes: sarcastic about a profession of faith. Satirical suggests expressing scorn or ridicule by saying the opposite of what one means: a satirical attack on his political promises.
1580s, "resembling Cynic philosophers," from cynic + -al (1). By late 17c. the meaning had shaded into the general one of "critical, disparaging the motives of others, captious, sneering, peevish." Related: Cynically.