Name for geometry that differs by a translation I have a simplistic question:  If I have two triangles, and there exists a translation that makes them equivalent (all their vertices would be the same after the translation), then is there a special term in geometry that I would use to describe the relationship between the two triangles?
We say that one triangle is the translate of the other. You could also say that they are translationally equivalent.
Yes, there is.

We say that the triangles (or shapes in general) are congruent. The relationship is known as congruency.