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

Etymology

Origin of first quarter

First recorded in 1905–10

Example Sentences

See Examples For:

first quarter

Baldwin said its board has already approved the deal, which is expected to close in the first quarter of 2027.

From The Wall Street Journal ● Sep. 14, 2026

However, the vast majority of families who apply for this support are unsuccessful - with national figures for the first quarter of 2026 showing only about one in six applications was deemed eligible, external.

From BBC ● Sep. 13, 2026

The Eagles’ only touchdown came on a 15-yard Aaron Hernandez touchdown reception in the first quarter after the Pirates lost possession by touching a punt and not recovering the ball.

From Los Angeles Times ● Sep. 12, 2026

Oracle shares jumped close to 6% premarket after posting a 60% surge in profits for the fiscal first quarter.

From The Wall Street Journal ● Sep. 11, 2026

The Lakers had a five-point lead after the first quarter, but I was too nervous to pay much attention to the game.

From "The Million Dollar Shot" by Dan Gutman