first quarter

American  

noun

Astronomy.

• first quarters
  plural

1. the instant, approximately one week after a new moon, when one half of the moon's disk is illuminated by the sun.

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first quarter British  

noun

1. one of the four principal phases of the moon, occurring between new moon and full moon, when half of the lighted surface is visible from earth Compare last quarter

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Other Word Forms

Noun Inflected Forms

• first quarters
  plural

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Etymology

Origin of first quarter

First recorded in 1905–10

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Example Sentences

See Examples For:

first quarter

But as he so often does, Doncic went to work in the first quarter, terrorizing Lendeborg and the Warriors’ faithful with 21 points.

From Los Angeles Times ● Oct. 31, 2026

For Alphabet, "this is the first quarter that the negative thesis around AI crushing search has legs," Ives wrote, referring to Google’s search advertising business, one of the most profitable businesses in history.

From Barron's ● Oct. 30, 2026

The other services saw the drop narrow from 21% in the first quarter to a decline of 18% in the second quarter, according to the study.

From MarketWatch ● Oct. 29, 2026

The deal, which carries an enterprise value of $15.3 billion, is slated to close in the first quarter of 2027.

From The Wall Street Journal ● Oct. 29, 2026

“You’re all wrong. The best play of the game was clearly the fumble on that third down in the first quarter and that’s because...”

From "The Benefits of Being an Octopus" by Ann Braden

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