Imperial units, the unit system many Americans still rely on, even though its retarded.

One who has a mania for music.

Retard Units is an unofficial synonym for "imperial measurements". As the rest of the world use metrics, the internet culture started mocking the medieval traditions of the Americans, and how little sense the usage of imperials pose compared to metrics.

when a lot of retards get together and start thier own unit. most of them need wheelchairs or zimmer frames to move. they can use thier walking sticks as shotgun when anouther unit drives up on thier turf. the reatrd unit often perform drive-bys on thier wheel chairs, and some times have drag races in thier wheel chairs modded with nitrous oxided that can get up to speeds of 150 mph.

What pretentious @#$%heads from Europe usually call the imperial system. It's simply a way of saying imperial system of measurement if you're a pretentious twat waffle.