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Synonyms

defining

American  
[dih-fahy-ning] / dɪˈfaɪ nɪŋ /

adjective

  1. decisive; critically important.

    Taking a course in architecture was a defining turn in her life.


Other Word Forms

  • nondefining adjective
  • self-defining adjective

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.

Apple had a history defining first 50 years.

From Barron's • Mar. 31, 2026

Education, the defining aspiration of the Indian middle class, has stopped delivering on its promise.

From BBC • Mar. 29, 2026

From age to age, defining what makes a Forsyte has grown trickier.

From Salon • Mar. 28, 2026

“The defining story of this Saturday’s mobilization is not just how many people are protesting — but where they are protesting,” Leah Greenberg, co-founder of Indivisible, said during the press briefing.

From Los Angeles Times • Mar. 28, 2026

What was really just a theatrical side show was now being enshrined in memory as the defining moment in the revolutionary drama.

From "Founding Brothers: The Revolutionary Generation" by Joseph J. Ellis