circumhorizontal arc
noun
cir·cum·horizontal arc
Definition of circumhorizontal arc
: a colored halo of 90° extent or less that is red on the upper side, parallel to the horizon and 46° or a little more below the sun, and produced by the refraction of light across 90° angles at the undersides of ice crystals in suspension in the air
From the M-W Editors
There's more!
Love words? You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.
Start your free trial today and get unlimited access to America's largest dictionary, with:
- More than 250,000 words that aren't in our free dictionary
- Expanded definitions, etymologies, and usage notes
- Advanced search features
- Ad free!
Seen and Heard
What made you want to look up circumhorizontal arc? Please tell us where you read or heard it (including the quote, if possible).
Writing? Check your grammar now!