Mathematics. of or pertaining to two numbers related by a congruence.
3.
Geometry. coinciding at all points when superimposed: congruent triangles.
Origin: 1375–1425; late ME < L congruent- (s. of congruēns, prp. of congruere to come together, fit in, agree), equiv. to con-con-+ -gru- base of uncert. meaning (attested only in this v. and ingruere to fall upon) + -ent--ent
1432, from L. congruentem (nom. congruens), prp. of congruere "to come together, agree, correspond with," from com- "with" + *gruere, *ruere "fall, rush."