first quarter

American  

noun

Astronomy.

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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Etymology

Origin of first quarter

First recorded in 1905–10

Example Sentences

Doncic had just five points in the first quarter.

From Los Angeles Times • Apr. 2, 2026

General Motors sold about 26,000 electric vehicles in the first quarter, a 19% decrease from a year ago and flat with the prior quarter.

From Barron's • Apr. 2, 2026

Elsewhere in the markets, shares of Tesla were down more than 5% after the company reported that deliveries were up in the first quarter but below Wall Street estimates.

From The Wall Street Journal • Apr. 2, 2026

Corporate earnings in the first quarter still could take “a bit of a hit, but the second quarter could be saved,” Conning’s Beaulieu said.

From MarketWatch • Apr. 2, 2026

But halfway through the first quarter, with the score tied at 10, Coach sent me in.

From "The Absolutely True Diary of a Part-Time Indian" by Sherman Alexie