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dichroism |
Noun
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pleochroism of a crystal so that it exhibits two different colors when viewed from two different directions |
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digenesis |
Noun
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alternation of sexual and asexual generations |
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diffraction |
Noun
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when light passes sharp edges or goes through narrow slits the rays are deflected and produce fringes of light and dark bands |
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direct current |
Noun
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an electric current that flows in one direction steadily |
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direct electric current |
Noun
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an electric current that flows in one direction steadily |
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doldrums |
Noun
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a belt of calms and light winds between the northern and southern trade winds of the Atlantic and Pacific |
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doldrums |
Noun
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a state of inactivity (in business or art etc) |
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double bond |
Noun
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a covalent bond in which two pairs of electrons are shared between two atoms |
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dust devil |
Noun
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a miniature whirlwind strong enough to whip dust and leaves and litter into the air |
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dative bond |
Noun
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a covalent bond in which both electrons are provided by one of the atoms |
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dust storm |
Noun
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a windstorm that lifts up clouds of dust or sand |
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depolarization |
Noun
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a loss of polarity or polarization |
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depolarisation |
Noun
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a loss of polarity or polarization |
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dimorphism |
Noun
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(biology) the existence of two forms of individual within the same animal species (independent of sex differences) |
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dimorphism |
Noun
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(chemistry) the property of certain substances that enables them to exist in two distinct crystalline forms |
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dipole moment |
Noun
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the moment of a dipole |
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downpour |
Noun
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a heavy rain |
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drizzle |
Noun
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very light rain |
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drizzle |
Verb
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moisten with fine drops |
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drizzle |
Verb
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rain lightly |
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double refraction |
Noun
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splitting a ray into two parallel rays polarized perpendicularly |
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diamagnetism |
Noun
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phenomenon exhibited by materials like copper or bismuth that become magnetized in a magnetic field with a polarity opposite to the magnetic force |
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diamond dust |
Noun
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small crystals of ice |
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domatium |
Noun
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a part of a plant (e.g., a leaf) that has been modified to provide protection for insects or mites or fungi |
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downdraft |
Noun
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a strong downward air current |
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dynamic electricity |
Noun
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a flow of electric charge |
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diurnal parallax |
Noun
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the parallax of a celestial body using two points on the surface of the earth as the earth rotates |
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dilleniid dicot family |
Noun
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family of more or less advanced dicotyledonous trees and shrubs and herbs |
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dicot genus |
Noun
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genus of flowering plants having two cotyledons (embryonic leaves) in the seed which usually appear at germination |
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dilleniid dicot genus |
Noun
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genus of more or less advanced dicotyledonous trees and shrubs and herbs |
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dioon |
Noun
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any cycad of the genus Dioon |
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dicot family |
Noun
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family of flowering plants having two cotyledons (embryonic leaves) in the seed which usually appear at germination |
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deodar |
Noun
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tall East Indian cedar having spreading branches with nodding tips |
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deodar cedar |
Noun
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tall East Indian cedar having spreading branches with nodding tips |
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drooping juniper |
Noun
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small tree of western Texas and mountains of Mexico having spreading branches with drooping branchlets |
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douglas fir |
Noun
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tall evergreen timber tree of western North America having resinous wood and short needles |
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douglas fir |
Noun
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strong durable timber of a douglas fir |
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douglas spruce |
Noun
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lofty douglas fir of northwestern North America having short needles and egg-shaped cones |
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douglas pine |
Noun
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lofty douglas fir of northwestern North America having short needles and egg-shaped cones |
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douglas hemlock |
Noun
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lofty douglas fir of northwestern North America having short needles and egg-shaped cones |
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dawn redwood |
Noun
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large fast-growing Chinese monoecious tree having flat bright-green deciduous leaves and small globular cones |
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dundathu pine |
Noun
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Australian timber tree resembling the kauri but having wood much lighter in weight and softer |
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daughter cell |
Noun
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a cell formed by the division or budding of another cell |
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dicot |
Noun
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flowering plant with two cotyledons |
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dicotyledon |
Noun
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flowering plant with two cotyledons |
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doll's eyes |
Noun
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North American herb with white poisonous berries |
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delphinium |
Noun
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any plant of the genus Delphinium having palmately divided leaves and showy spikes of variously colored spurred flowers |
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dutch clover |
Noun
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creeping European clover having white to pink flowers and bright green leaves |
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desert rose |
Noun
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South African shrub having a swollen succulent stem and bearing showy pink and white flowers after the leaves fall |
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dita |
Noun
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evergreen tree of eastern Asia and Philippines having large leathery leaves and small green-white flowers in compact cymes |