Word Study
placoid
WORDNET DICTIONARY
Adjective placoid has 1 sense
- placoid(s = adj.all) platelike - as the hard flattened scales of e.g. sharks; Array
CIDE DICTIONARY
placoid, a. [Gr. pla`x, plako`s, a tablet + -oid.].
Platelike; having irregular, platelike, bony scales, often bearing spines; pertaining to the placoids. [1913 Webster]
placoid, n.
Any fish having placoid scales, as the sharks. [1913 Webster]
OXFORD DICTIONARY
placoid, adj. & n.
--adj.
1 (of a fish-scale) consisting of a hard base embedded in the skin and a spiny backward projection (cf. CTENOID).
2 (of a fish) covered with these scales.
--n. a placoid fish, e.g. a shark.
--adj.
1 (of a fish-scale) consisting of a hard base embedded in the skin and a spiny backward projection (cf. CTENOID).
2 (of a fish) covered with these scales.
--n. a placoid fish, e.g. a shark.
Etymology
Gk plax plakos flat plate
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