Placoidei

plural noun

Pla·​coi·​dei

-dēˌī

in former classifications

: a group of fishes with placoid scales equivalent or nearly so to Chondrichthyes and sometimes including the cyclostomes

Word History

Etymology

New Latin, from plac- + -oidei

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