frostbow

noun

: a white arc in the sky that occurs in frosty weather and is formed by reflection of sunlight from floating ice crystals : the parhelic circle that has its center at the zenith and is not to be confused with the white rainbow

Word History

First Known Use

1841, in the meaning defined above

The Ultimate Dictionary Awaits

Expand your vocabulary and dive deeper into language with Merriam-Webster Unabridged.

1. Expanded definitions
2. Detailed etymologies
3. Advanced search tools
4. All ad-free

Discover what makes Merriam-Webster Unabridged the essential choice for true word lovers.

Start Your Free Trial Now