Here you will find one or more explanations in English for the word Placoid.
Also in the bottom left of the page several parts of wikipedia pages related to the word Placoid and, of course, Placoid synonyms and on the right images related to the word Placoid.
Placoid
Placoid Plac"oid, a. [Gr. ?, ?, a tablet + -oid.] (Zo["o]l.)
Platelike; having irregular, platelike, bony scales, often
bearing spines; pertaining to the placoids.
Placoid
Placoid Plac"oid, n. (Zo["o]l.)
(a) Any fish having placoid scales, as the sharks.
(b) One of the Placoides.
Meaning of Placoid from wikipedia