Damage

A blot is an uneven spot or stain. When you say blot, you usually mean a blot of ink on paper.

Something is broken if it is so badly damaged it can't be used for its original purpose. For example, a chair is broken if a leg has come off and you can't sit on it. The cup in the picture is shattered so badly it no longer holds coffee. Some things that are broken can be fixed, but not all.

Corroding is the process by which something becomes corroded. Metals usually corrode by a slow chemical reaction.

Corrosion is what appears on something that is corroded, or the process of something becoming corroded.

A crease is a line that has been made in a surface, usually by bending or folding it. People get creases in their skin in places that move, like around their eyes. The piece of paper in the picture has creases in it from where someone has folded it into the shape of a paper plane.

Debris is the broken remains of something that has been destroyed, usually from a natural event like a tornado but debris can be created by any kind of destruction.

A defect is something wrong with something, that stops it from being perfect. A defect in a machine might stop it from working at all.
A defect might also be called a flaw or imperfection.

A dent is a hollow, like a shallow hole in a surface. Dents are usually caused by hitting something. The car in the picture has a dent in its side.

Destruction is the act of destroying or demolishing something. It might also be used to describe the remains left once something has been destroyed.

A fissure is a relatively deep, narrow hole in something. Some fissures are natural features of things, others are caused by external damage.