American

American is a sub-language of English. It was first used by those in the United States after the Dawn War which left the US isolated from the rest of the world.

The term was first coined by Professor George Baldwin in 2209, a psychology expert who worked in the Chicago wastelands as a psychologist who dealt with mental illnesses in people who'd been mentally hurt (Friends being murdered, Homes destroyed etc.), after hearing the arrival signal of the Garden ship who spoke in a way that he could only vaguely understand yet knew this was the same language he spoke.

After that American became the official language of the United States of America in 2488, the year the recovery period started. Since then American English has already diverted very far from British English enough that one simply couldn't understand the other (They were about as similar as German is to English).