n. [ Gr. &unr_; thick, crowded + &unr_;, &unr_;, a tooth. ] (Paleon.) Any fossil fish belonging to the Pycnodontini. They have numerous round, flat teeth, adapted for crushing. [ 1913 Webster ]

‖n. pl. [ NL. ] (Zool.) An extinct order of ganoid fishes. They had a compressed body, covered with dermal ribs (pleurolepida) and with enameled rhomboidal scales. [ 1913 Webster ]

n. (Zool.) One of the Pycnogonida. [ 1913 Webster ]

‖n. pl. [ NL., fr. Gr. &unr_; thick crowded + &unr_; knee. ] (Zool.) A class of marine arthropods in which the body is small and thin, and the eight legs usually very long; -- called also Pantopoda. [ 1913 Webster ]

☞ The abdomen is rudimentary, and the triangular mouth is at the end of a tubular proboscis. Many of them live at great depths in the sea, and the largest of them measure two feet across the extended legs. [ 1913 Webster ]

n. [ Gr. &unr_; dense, compact + -meter. ] (Physics) A specific gravity bottle; a standard flask for measuring and comparing the densities of liquids. [ Also written pyknometer. ] [ 1913 Webster ]

a. [ Gr. &unr_; with the pillars close together; &unr_; close + &unr_; a column, pillar: cf. F. pycnostyle. ] (Anc. Arch.) See under Intercolumniation. -n. A pycnostyle colonnade. [ 1913 Webster ]