Defn: Multiplying or magnifying sound.
— n.
Defn: A polyacoustic instrument.
POLYACOUSTICS
Pol`y*a*cous"tics, n.
Defn: The art of multiplying or magnifying sounds.
POLYACRON Pol`y*a"cron, n.; pl. Polyacra, E. Polyacrons. Etym: [NL., fr. Gr. poly`s many + 'a`kron summit.] (Geom.)
Defn: A solid having many summits or angular points; a polyhedron.
POLYACTINIA
Pol`y*ac*tin"i*a, n. pl. Etym: [NL. See Poly-, and Actinia.] (Zoöl.)
Defn: An old name for those Anthozoa which, like the actinias, have numerous simple tentacles.
POLYADELPHIA
Pol`y*a*del"phi*a, n. pl. Etym: [NL., fr. Gr. (Bot.)
Defn: A Linnæan class of plants having stamens united in three or more bodies or bundles by the filaments.