Antonym: pessimism. Similar words: optimistic, optimum, animism, option, adoption, optician, optic nerve, timid. Meaning: ['ɑptɪmɪzm /'ɒp-] 
n. 1. the optimistic feeling that all is going to turn out well 2. a general disposition to expect the best in all things.
n. 1. the optimistic feeling that all is going to turn out well 2. a general disposition to expect the best in all things. 151. UN officials are expressing cautious optimism that the latest cease-fire is holding.
152. Optimism about the US economy has been a rare commodity lately.
153. Their optimism is apt to be decidedly conditional and tremulous.
More similar words: optimistic, optimum, animism, option, adoption, optician, optic nerve, timid, timing, timidly, intimidate, pessimistic, dismiss, skepticism, intimidation, intimidating, dismissal, euphemism, dismissed, misconception, from time to time, opt, adopt, opt for, adopted, helicopter, mimi, limit, mimic, simile.