first quarter

American

noun

Astronomy.

the instant, approximately one week after a new moon, when one half of the moon's disk is illuminated by the sun.

first quarter British

noun

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of first quarter

First recorded in 1905–10

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Official figures record a contraction in the eurozone economy in the first quarter.

From The Wall Street Journal • Jun. 15, 2026

The new outlook came as the furniture company continued to navigate industry headwinds during its fiscal first quarter, Chief Executive Shawn David Nelson said.

From The Wall Street Journal • Jun. 15, 2026

In the first quarter of 2026, official data put growth at 5.6 percent, but analysts have expressed doubts about the reliability of the figures.

From Barron's • Jun. 14, 2026

The Spurs became the first team to lead five finals games by at least 10 points in the first quarter.

From BBC • Jun. 14, 2026

During the first quarter of each home game, Stargirl went over to the visitors’ section and gave them a cheer.

From "Stargirl" by Jerry Spinelli

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023