[va.lence] n [LL valentia power, capacity, fr. L valent-, valens, prp. of valere to be strong--more at wield] (1884) 1: the degree of combining power of an element as shown by the number of atomic weights of a univalent element (as hydrogen) with which the atomic weight of the element will combine or for which it can be substituted or with which it can be compared
2. a: relative capacity to unite, react, or interact (as with antigens or a biological substrate) b: the degree of attractiveness an individual, activity, or object possesses as a behavioral goal