Definition: the act of putting one thing or person in the place of another: "he sent Smith in for Jones but the substitution came too late to help"
Similar words: change
Definition: the action of changing something
Usage: the change of government had no impact on the economy; his change on abortion cost him the election
Definition: an event in which one thing is substituted for another
Usage: the replacement of lost blood by a transfusion of donor blood
Definition: an instance of change; the rate or magnitude of change