Cv, the flow coefficient, used to determine the pressure-drop across an element in fluid flow applications cv, the specific heat of a material at constant volume Calorific value, the amount of heat released during the combustion of a substance Cataclysmic variable star, characterized by irregular and large increases in brightness Coefficient of variation, a measure of dispersion of a probability distribution Compensating variation, an economic concept of compensation for a price change Constant-velocity joint, or CV-joint Consonant–vowel, an open-syllable pattern in linguistics Contractile vacuole, an organelle found in some cells Cultivated variety or cultivar Cyclic voltammetry, an electrochemical way of measuring