Wortnetzwerk: constant

Continually or regularly over a long time.

(physics) the universal constant relating force to mass and distance in Newton's law of gravitation

(chemistry) the ratio of concentrations when equilibrium is reached in a reversible reaction (when the rate of the forward reaction equals the rate of the reverse reaction)

Not any of a group of people or things. It represents zero or a total lack of something that was mentioned or is being discussed.