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

Final sales rose at a modest 1.7% annual pace in the first quarter, below the 2.5% average per quarter since 2022.

From MarketWatch ● Jul. 29, 2026

Meta’s free cash flow shrank to less than $784 million in the second quarter, down from more than $12 billion in the first quarter.

From The Wall Street Journal ● Jul. 29, 2026

Ionescu scored 14 points in the first quarter, propelling the visitors to a 36-30 lead.

From Los Angeles Times ● Jul. 29, 2026

If the forecast is correct, GDP would fall short of the 2.1% increase in the first quarter.

From MarketWatch ● Jul. 29, 2026

At the end of the first quarter, the Celtics were up by three.

From "Millionaires for the Month" by Stacey McAnulty