/i kway"zheuhn, -sheuhn/ , n.
1. the act of equating or making equal; equalization: the symbolic equation of darkness with death.
2. equally balanced state; equilibrium.
3. Math. an expression or a proposition, often algebraic, asserting the equality of two quantities.
4. Chem. a symbolic representation showing the kind and amount of the starting materials and products of a reaction.
[ 1350-1400; ME aequation- (s. of aequatio ) an equalizing. See EQUATE, -ION ]