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optimism

American  
[op-tuh-miz-uhm] / ˈɒp təˌmɪz əm /

noun

  1. a disposition or tendency to look on the more favorable side of events or conditions and to expect the most favorable outcome.

    Synonyms:
    cheerfulness, hopefulness, confidence
    Antonyms:
    cynicism, pessimism
  2. the belief that good ultimately predominates over evil in the world.

    Antonyms:
    cynicism, pessimism
  3. the belief that goodness pervades reality.

  4. the doctrine that the existing world is the best of all possible worlds.


optimism British  
/ ˈɒptɪˌmɪzəm /

noun

  1. the tendency to expect the best and see the best in all things

  2. hopefulness; confidence

  3. the doctrine of the ultimate triumph of good over evil

  4. the philosophical doctrine that this is the best of all possible worlds

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • antioptimism noun
  • optimist noun
  • optimistic adjective
  • optimistically adverb
  • overoptimism noun

Etymology

Origin of optimism

First recorded in 1730–40; from French optimisme, from Latin optim(um) ( optimum ) + French -isme -ism

Explanation

Optimism is all about seeing the bright side of things. If you think it’s going to be a great day, even though the bills are due, you lost your wallet, and you forgot your lunch, then you're full of optimism. Optimism is expecting that the best will happen. It comes from the Latin word optimus, which means "best." Even if you don’t think the very best thing will always happen, if you're generally given to optimism, you think things will get better instead of worse. The opposite of optimism is pessimism, which is the expectation that everything will go wrong, or is wrong.

Keep Reading on Vocabulary.com

Vocabulary lists containing optimism

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Oil prices nudged below $95 a barrel and U.S. stock futures were flat in placid early European trade, amid investor optimism around U.S.-Iran peace talks this week.

From The Wall Street Journal • Apr. 15, 2026

Crypto-related stocks surged Tuesday, driven by investor optimism for a U.S.-Iran peace deal boosting digital assets.

From Barron's • Apr. 14, 2026

Investors watch oil prices closely as a sudden spike can lead to a recession, he said, but recent trading action highlighted optimism that the energy-supply disruption triggered by the Iran conflict might be short-lived.

From MarketWatch • Apr. 14, 2026

When this war started, I expressed cautious optimism that it would be successful.

From The Wall Street Journal • Apr. 13, 2026

In a true reflection of his optimism, he’d recently put his name in for a promotion.

From "Becoming" by Michelle Obama