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

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

In the Southern Section Division 1 final against Corona Centennial at the Rose Bowl, Palmer put the ball in Mosley’s hands on every play in the first quarter.

From Los Angeles Times ● Sep. 11, 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 markets still expect this to be imminent with fourth quarter of 2026 and first quarter of 2027 the most frequent responses.

From MarketWatch ● Sep. 9, 2026

For the first time all year, we were trailing at the end of the first quarter.

From "Stargirl" by Jerry Spinelli