the luminous region between the Faraday dark space and the anode glow in a vacuum tube, occurring when the pressure is low.
- Positive convergence
positive convergence n. The inward deviation of the visual axes.
noun, Automotive. 1. a means of reducing air pollution by directing the fumes from the crankcase of an engine into the intake manifold, so that they will be channeled into the cylinders and burned. Abbreviation: PCV.
- Positive declination
positive declination n. See extorsion.
adjective, Mathematics. 1. (of a quadratic form) positive for all real values of the variables, where the values are not all zero. 2. (of a matrix) displaying the coefficients of a positive definite quadratic form.