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

Solar eclipses occur during the monthly new moon phase, when the lunar disk passes directly between the sun and Earth in its slightly lopsided orbit, casting its colossal shadow over a swathe of our planet's surface. — Anthony Wood, Space.com, 5 Aug. 2026

The same new moon responsible for the eclipse will leave the night sky free from moonlight as the Perseid meteor shower reaches its annual maximum. — Jamie Carter, Forbes.com, 2 Aug. 2026

Astrologically, solar eclipses are equivalent to a super potent new moon, and are often associated with new beginnings, redirections and chapters that continue developing over time. — Valerie Mesa, PEOPLE, 28 July 2026

Plus, this year, the shower will peak during a new moon, providing ideal dark skies for viewing. — Michele Laufik, Martha Stewart, 17 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