Other forms: aftermaths
The aftermath of a car crash might include a broken fender, a sprained rib, and a lecture from a police officer. The consequences of an unpleasant event make up its aftermath.
The math in aftermath does not refer to adding or subtracting numbers, rather it is related to a Germanic word for mowing, or harvest. If you have been mowed down by a class of excited first graders, the aftermath might be a bruised knee, a headache from all of the squealing, and red face from embarrassment.