specific-gravity bulb

noun

: a hollow glass bulb so weighted that it will float on a liquid of greater and sink in a liquid of less specific gravity than that marked on the bulb

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