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gall, in botany

(Encyclopedia)gall, abnormal growth, or hypertrophy, of plant tissue produced by chemical or mechanical (e.g., the rubbing together of two branches) irritants or hormones. Chemical irritants are released by parasit...

Hyades, in astronomy

(Encyclopedia)Hyades hīˈədēz [key], in astronomy, open star cluster in the constellation Taurus, located immediately to the right of the bright star Aldebaran. The cluster is about 130 light-years from the eart...

hail, in meteorology

(Encyclopedia)hail, precipitation in the form of pellets composed of ice or of ice and snow, occurring at any time of the year, usually during the passage of a cold front or during a thunderstorm. Small hailstones ...

mine, in warfare

(Encyclopedia)mine, in warfare, term formerly applied to a system of tunnels dug under an army fortification and ending in a chamber where either explosives were placed to be detonated at a chosen moment or the sup...

Titan , in astronomy

(Encyclopedia)Titan tīˈtən [key], in astronomy, the largest of the named moons, or natural satellites, of Saturn. Also known as Saturn VI (or S6), Titan is 3,200 mi (5,150 km) in diameter, orbits Saturn at a mea...

impressionism, in painting

(Encyclopedia)impressionism, in painting, late-19th-century French school that was generally characterized by the attempt to depict transitory visual impressions, often painted directly from nature, and by the use ...

rocket, in aeronautics

(Encyclopedia)CE5 Relative positions of the components of the Saturn V rocket, the U.S. space vehicle used in the moon missions rocket, any vehicle propelled by ejection of the gases produced by combustion of s...

note, in music

(Encyclopedia)note, in musical notation, symbol placed on or between the lines of a staff to indicate the pitch and the relative duration of the tone to be produced by voice or instrument. The largest note value in...

conjunction, in astronomy

(Encyclopedia)conjunction, in astronomy, alignment of two celestial bodies as seen from the earth. Conjunction of the moon and the planets is often determined by reference to the sun. When a body is in conjunction ...

Pan, in astronomy

(Encyclopedia)Pan, in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn XVIII (or S18), Pan is 12.5 mi (20 km) in diameter, orbits Saturn at a mean distance of 83,000 mi (133...