constant quantity(n = noun.cognition) constant, invariable - a quantity that does not vary;
is a kind of quantity
has particulars: parameter, parametric quantity

boltzmann's constant, complex quantity, constant, constant lambert, constant of gravitation, constant of proportionality, cosmological constant, definite quantity, dissociation constant, equilibrium constant, fundamental quantity, gas constant, gravitational constant, hubble constant, hubble's constant, indefinite quantity, large indefinite quantity, law of constant proportion, leonard constant lambert, numerical quantity, parametric quantity, planck's constant, prime quantity, quantity, quantity unit, relative quantity, rydberg constant, small indefinite quantity, solar constant, time constant, universal gas constant, universal gravitational constant, unknown quantity, variable quantity