plac·​oid ˈpla-ˌkȯid How to pronounce placoid (audio)
: of, relating to, or being a scale of dermal origin with an enamel-tipped spine characteristic of the elasmobranchs

Word History


Greek plak-, plax flat surface

First Known Use

1842, in the meaning defined above

Time Traveler
The first known use of placoid was in 1842

Dictionary Entries Near placoid

Cite this Entry

“Placoid.” Dictionary, Merriam-Webster, Accessed 31 Mar. 2023.

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