first quarter

American  

noun

Astronomy.

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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Etymology

Origin of first quarter

First recorded in 1905–10

Example Sentences

The company reported stronger fundraising for its smaller businesses in the first quarter, offsetting stalled growth in its flagship private-credit unit.

From The Wall Street Journal • May 1, 2026

Used electric vehicle sales increased 20% in the first quarter this year compared to last as prices at the pump continue to climb.

From Los Angeles Times • May 1, 2026

Momentum likely peaked in the first quarter and may moderate as higher energy costs and fiscal consolidation weigh on growth.

From The Wall Street Journal • May 1, 2026

Chevron earnings are expected to fall 56% in the first quarter from a year ago, which makes little sense given that oil prices are up more than 70% this year.

From Barron's • Apr. 30, 2026

But leaving the bench in the first quarter is unheard of.

From "Boy21" by Matthew Quick