Placoid
Placoid , adjective
[Greek pla`x, plako`s, a tablet + -oid.]
(Zoology) Platelike; having irregular, platelike, bony scales, often bearing spines; pertaining to the placoids.
Placoid , noun
(a)
(Zoology) Any fish having placoid scales, as the sharks.
(b)
(Zoology) One of the Placoides.