Edge (ěj). An edge is any 1-dimensional area on a polytope. It is usually seen as a line. An edge is where two opposite planes meet at an undefined angle. You can find an edge on every n-dimensional (where n≥1) object, except for objects such as circles, spheres, hyperspheres etc. An edge is measured in a base unit of metres. File:Square pyramid.png This geometry-related article contains minimal information concerning its topic. You can help the Mathematics Wikia by adding to it.