underdrain

1 of 2

noun

: a concealed drain with openings through which the water enters when the water table reaches the level of the drain

an underdrain below a filter bed

underdrain

2 of 2

transitive verb

: to drain by forming an underdrain

underdrain a meadow

Word History

Etymology

Noun

under entry 3 + drain

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