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 Huskies only scored again on the freak safety in the first quarter.

From Los Angeles Times ● Sep. 12, 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

There were an estimated 981,000 so-called Neets, aged 16 to 24, in April to June, a fall of 30,000 compared with the first quarter of the year.

From BBC ● Sep. 7, 2026

The company says the campaign has boosted demand, with natural diamond sales at U.S. independent jewelry retailers increasing 9% in the first quarter of 2026.

From The Wall Street Journal ● Sep. 5, 2026

For most of the first quarter of the century, the eastern colleges thoroughly dominated the regatta.

From "The Boys in the Boat: Nine Americans and Their Epic Quest for Gold at the 1936 Berlin Olympics" by Daniel James Brown