old moon

American  

noun

1. waning moon.

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old moon British  

noun

1. a phase of the moon lying between last quarter and new moon, when it appears as a waning crescent

2. the moon when it appears as a waning crescent

3. the time at which this occurs

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Etymology

Origin of old moon

First recorded in 1580–90

Example Sentences

Earthshine is also called “the old moon in the new moon’s arms”—a lovely turn of phrase that not nearly enough astronomers use.

From Scientific American • Jul. 21, 2023

The expedition also collected some especially old moon rocks.

From Washington Post • Apr. 21, 2022

The big old moon of a few days back had shrunk to something with a big slice of itself gone.

From "In the Time of the Butterflies" by Julia Alvarez

“That boy’s right! We could mine that old moon good!”

From "October Sky" by Homer Hickam

Now and again we caught glimpses of the dim lights in farms, and once we saw the old moon reflected in the Volga.

From The Image and the Likeness by Campbell, John Scott