new moon

noun

1

: the moon's phase when it is in conjunction with the sun so that its dark side is toward the earth

also : the thin crescent moon seen shortly after sunset for a few days after the actual occurrence of the new moon phase

2

: the beginning of each Jewish month marked by a special liturgy

Examples of new moon in a Sentence

Recent Examples on the Web

According to online clock Time and Date, the comet’s visit will coincide with a new moon, providing perfect viewing conditions. — Alexiah Syrai Olsen, Sacbee.com, 7 July 2026

Fortunately, a new moon on July 14 offers the best opportunity for skywatchers to search for the Milky Way, NASA explained in a monthly skywatching guide. — Eric Lagatta, USA Today, 2 July 2026

July’s Milky Way Window The most important observing period of July begins after the last-quarter moon on July 7 and continues through the nights around new moon on July 14. — Jamie Carter, Forbes.com, 1 July 2026

Your best chances for unimpeded views of the night sky will come just before and after the arrival of July’s new moon on the 14th. — Michael D'estries, Travel + Leisure, 1 July 2026

Word History

First Known Use

before the 12th century, in the meaning defined at sense 1

Rhymes for new moon

• attune
• baboon
• balloon
• bassoon
• buffoon
• cartoon
• cocoon
• festoon
• gaboon
• harpoon
• immune
• impugn

Kids Definition

new moon

noun

: the moon's phase when its dark side is toward the earth

also : the thin curved outline of the moon seen shortly after sunset for a few days after the actual occurrence of the new moon phase