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pitch, in music

(Encyclopedia)pitch, in music, the position of a tone in the musical scale, today designated by a letter name and determined by the frequency of vibration of the source of the tone. Pitch is an attribute of every m...

Pleiades, in astronomy

(Encyclopedia)Pleiades plēˈədēz, plīˈ– [key], in astronomy, famous open star cluster in the constellation Taurus; cataloged as M45. The cluster consists of some 500 stars, has a diameter of 35 light-years, ...

plum, in botany

(Encyclopedia)plum, common name for a tree of any of many species of the genus Prunus of the family Rosaceae (rose family) and for its fruit, a drupe. The plum is generally cultivated in the temperate zones, though...

Pluto, in astronomy

(Encyclopedia)Pluto, in astronomy, a dwarf planet and the first Kuiper belt, or transneptunian, object (see comet) to be discovered (1930) by astronomers. Pluto has an elliptical orbit usually lying beyond that of ...

pod, in aviation

(Encyclopedia)pod, in aviation: see airplane.

pod, in botany

(Encyclopedia)pod or legume, dehiscent fruit of a member of the family Leguminosae (pulse family). At maturity the pod splits along its two seams and releases the enclosed seeds. ...

power, in mathematics

(Encyclopedia)power, in mathematics: see exponent. ...

precipitation, in chemistry

(Encyclopedia)precipitation, in chemistry, a process in which a solid is separated from a suspension, sol, or solution. In a suspension such as sand in water the solid spontaneously precipitates (settles out) on st...

precipitation, in meteorology

(Encyclopedia)precipitation, in meteorology, condensed moisture that falls to the surface of the earth in the form of rain, sleet, snow, hail, frost, or dew. ...

phase, in astronomy

(Encyclopedia)CE5 Phases of the moon phase, in astronomy, the measure of how much of the illuminated surface of a planet or satellite can be seen from a point at a distance from that body; the term is most ofte...