blue billy

noun

: a petrel (Pachyptila desolata) of the southern oceans with a bluish back and white underparts

Word History

Etymology

probably from the name Billy

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