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thermal conductivity. n. 1. (General Physics) a measure of the ability of a substance to conduct heat, determined by the rate of heat flow normally through an area in the substance divided by the area and by minus the component of the temperature gradient in the direction of flow: measured in watts per metre per kelvin.
1. a particular mode of being of a person or thing; existing state; situation with respect to circumstances. 2. state of health: a patient in critical condition. 3. fit or requisite state: to be in no condition to run. 4. social position.