PYRAMIDOID
Py*ram"i*doid, n. Etym: [Gr. -id: cf. F. pyramidoïde.]

Defn: A solid resembling a pyramid; — called also pyramoid. Barlow.

PYRAMIS
Pyr"a*mis, n.; pl. Pyramides. Etym: [L.]

Defn: A pyramid.

PYRAMOID
Pyr"a*moid, n.

Defn: See Pyramidoid.

PYRARGYRITE
Py*rar"gy*rite, n. Etym: [Gr. (Min.)

Defn: Ruby silver; dark red silver ore. It is a sulphide of antimony and silver, occurring in rhombohedral crystals or massive, and is of a dark red or black color with a metallic adamantine luster.

PYRAZINE; PYRAZIN
Pyr"a*zine, n. Also -zin. [Pyridine + Gr. not + life.] (Org. Chem.)

Defn: A feebly basic solid, C4H4N2, obtained by distilling piperazine with zinc dust, and in other ways. Also, by extension, any of various derivatives of the same.