Adequation :: Adequation (n.) The act of equalizing; act or result of making adequate; an equivalent.
Equation :: Equation (n.) A making equal; equal division; equality; equilibrium.
Equation :: Equation (n.) An expression of the condition of equality between two algebraic quantities or sets of quantities, the sign = being placed between them; as, a binomial equation; a quadratic equation; an algebraic equation; a transcendental equation; an exponential equation; a logarithmic equation; a differential equation, etc..
Equation :: Equation (n.) A quantity to be applied in computing the mean place or other element of a celestial body; that is, any one of the several quantities to be added to, or taken from, its position as calculated on the hypothesis of a mean uniform motion, in order to find its true position as resulting from its actual and unequal motion..