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

ExxonMobil’s net earnings for the latest quarter totaled $14.53 billion, which was up 247% from the first quarter, and up 106% from a year ago.

From MarketWatch ● Jul. 31, 2026

Data Center Watch, a tracker run by AI intelligence firm 10a Labs, says at least 75 US projects worth some $130 billion were delayed or blocked in the first quarter of 2026.

From Barron's ● Jul. 31, 2026

Meanwhile, adjusted EPS rose to $3.52 from $2.09 in the first quarter but missed the average analyst estimate compiled by FactSet of $3.56.

From MarketWatch ● Jul. 31, 2026

Rivian delivered 12,194 EVs, up from 10,365 in the first quarter.

From The Wall Street Journal ● Jul. 30, 2026

“You’re all wrong. The best play of the game was clearly the fumble on that third down in the first quarter and that’s because...”

From "The Benefits of Being an Octopus" by Ann Braden