con·gru·ent / kənˈgroōənt; ˈkänggroōənt/ • adj. 1. in agreement or harmony: the rules are congruent with the requirements of the law.2. Geom. (of figures) identical in form; coinciding exactly when superimposed.DERIVATIVES: con·gru·ence n.con·gru·en·cy n.con·gru·ent·ly adv.

congruent conforming, accordant, agreeable. XV. — L. congruēns, -ent-, prp. of congruere meet together, agree, correspond, f. CON- + *gruere, ruere fall, rush; see RUIN, -ENT.
So congruity XV. — F. or late L. congruous XVI.