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tung•sten (ˈtʌŋ stən) n. a rare, bright gray, lustrous metallic element having a high melting point, 3410°C: used in electric-lamp filaments.
tung•sten
(ˈtʌŋ stən)
n.
a rare, bright gray, lustrous metallic element having a high melting point, 3410°C: used in electric-lamp filaments.

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Fluorescence (flo͝orĕs`əns), luminescence  in which light of a visible color is emitted from a substance under stimulation or excitation by light or other forms of electromagnetic radiation or by certain other means. The light is given off only while the stimulation continues;
Fluorescence
(flo͝orĕs`əns), luminescence
in which light of a visible color is emitted from a substance under stimulation or excitation by light or other forms of electromagnetic radiation or by certain other means. The light is given off only while the stimulation continues;

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watch and ward noun Definition of WATCH AND WARD 1 :  continuous unbroken vigilance and guard 2 :  service as a watchman or sentinel required from a feudal tenant
watch and ward
noun
Definition of WATCH AND WARD
1
: continuous unbroken vigilance and guard
2
: service as a watchman or sentinel required from a feudal tenant