[kroo k-uh-ree] /ˈkrʊk ə ri/
the activities and dealings of crooks; crooked practices.
noun, Physics. 1. the dark space between the cathode glow and the negative glow in a vacuum tube, occurring when the pressure is low.
[kroo k-sahyt] /ˈkrʊk saɪt/ noun 1. a rare mineral, selenide of copper, thallium, and silver, (Cu, Tl, Ag) 2 Se, occurring in steel-gray, compact masses.
- Crookes lens
noun 1. a type of lens, used in sunglasses, that is made from glass containing cerium. It reduces the transmission of ultraviolet radiation
noun, Optics. 1. (def 1). noun 1. (physics) a type of radiometer consisting of an evacuated glass bulb containing a set of lightweight vanes, each blackened on one side. The vanes are mounted on a vertical axis and revolve when light, or other radiant energy, falls on them