When actual cost exceed estimated cost with no change in scope, is it called cost overrun, cost risk or other?

Question

When actual cost exceed estimated cost with no change in scope, is it called cost overrun, cost risk or other?

Answer 1

The correct answer is:

when actual cost exceed estimated cost with no change in scope, is it called cost overrun.

Had there been a change of scope, it would be cost escalation due to scope change.