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placoid
plac·oid P0344000 (plăk′oid)adj.1. Platelike.2. a. Relating to or being a kind of fish scale that is a toothlike plate with a protruding spine, characteristic of sharks, skates, and rays.b. Having placoid scales.
[Greek plax, plak-, flat stone, plate; see plāk- in Indo-European roots + -oid.]placoid (ˈplækɔɪd) adj1. (Biology) platelike or flattened2. (Zoology) (of the scales of sharks and other elasmobranchs) toothlike; composed of dentine with an enamel tip and basal pulp cavity[C19: from Greek plac-, plax flat]plac•oid (ˈplæk ɔɪd)
adj. platelike, as the scales or dermal investments of sharks. [1835–45; < Greek plak- (s. of pláx) something flat, tablet] Thesaurus| Adj. | 1. | placoid - as the hard flattened scales of e.g. sharksplatelikeplanar, two-dimensional - involving two dimensions |
EncyclopediaSeedenticleplacoid
placoid [plak´oid] platelike or plaquelike.placoid (plăk′oid)adj. Platelike.placoid or denticle the dermal denticles of cartilaginous fish. Placoids are tooth-like structures of enamel, covered with dentine. Compare COSMOID, GANOID.placoid
Synonyms for placoidadj as the hard flattened scales of eSynonymsRelated Words |