new moon

noun

1. the moon either when in conjunction with the sun or soon after, being either invisible or visible only as a slender crescent.
2. the phase of the moon at this time.

noun

1. the moon when it appears as a narrow waxing crescent
2. the time at which this occurs
3. astronomy one of the four principal phases of the moon, occurring when it lies between the earth and the sun

1. The phase of the Moon that occurs when it passes between Earth and the Sun, making it either invisible or visible only as a thin crescent at sunset. See more at moon. Compare full moon.