umbral

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In math, Ono is known for his work on a range of topics across number theory, from Ramanujan’s congruences to the umbral moonshine conjecture.

From The Wall Street Journal • Dec. 4, 2025

The moon will gradually darken as our lunar companion cruises through Earth’s shadow — moving from the penumbral into the umbral phase.

From Washington Post • Oct. 30, 2021

The string theory underlying umbral moonshine is likely to be “not just any physical theory, but a particularly important one,” Cheng said.

From Scientific American • Apr. 7, 2015

The first partial eclipse phase starts at 1:58 a.m., when the moon enters Earth’s umbral shadow.

From Washington Post • Mar. 29, 2014

Outside the umbral cone is that of the penumbra, within which the sun is partially hidden by the moon.

From Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 10 "Echinoderma" to "Edward" by Various