prestomum

noun

pre·​sto·​mum

-məm

plural prestoma

-ōmə

also prestomums

: the cleft between the labellar lobes in front of the oral aperture in insects

Word History

Etymology

New Latin, from pre- + -stomum

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