defining

American  

[dih-fahy-ning] / dɪˈfaɪ nɪŋ /

adjective

1. decisive; critically important.

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

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Other Word Forms

• nondefining adjective
• self-defining adjective

Example Sentences

Merriam-Webster crowned “slop” as 2025’s word of the year in mid-December, defining it as “digital content of low quality that is produced usually in quantity by means of artificial intelligence.”

From Salon

He argued that by defining herself too well, Crockett has become unelectable.

From Salon

As with Odd Future, the New York collective used the multimedia richness and easily shareable content of Tumblr to build both a defining aesthetic and an air of mystique for its projects.

From The Wall Street Journal

One of the defining breakthroughs in mammal evolution was the rise of highly sensitive hearing.

From Science Daily

The situation has the potential to serve as a defining moment of Wirth’s legacy.

From The Wall Street Journal