Equations of condition
|(Math.)||equations formed for deducing the true values of certain quantities from others on which they depend, when different sets of the latter, as given by observation, would yield different values of the quantities sought, and the number of equations that may be found is greater than the number of unknown quantities.|
See also: Equation
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.