shell pump

noun

: a simple form of sand pump or sludger consisting of a hollow cylinder with a ball or clack valve at the bottom and used with a flush of water to remove detritus

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