Definition of old moon in US English:

old moon


  • The moon in its last quarter, before the new moon.

    • ‘We'd be old friends looking at an old moon, against the backdrop of lit-up Chicago.’
    • ‘There is a slice of new, or old moon in the sky to the east, with Mars still glowing orange in the west.’
    • ‘For those of you who saw that big old moon in the sky last night, with its full face aglow, you will understand.’