hubcap

Hubcap

A hubcap or hub cap is a decorative disk on an automobile wheel that covers at minimum the central portion of the wheel, called the hub.^[1] An automobile hubcap is used to cover the wheel hub and the wheel fasteners to reduce the accumulation of dirt and moisture. It also has the function of decorating the car.^[2]
A hubcap is technically a small cover over the center of the wheel, while a wheel cover is a decorative metal or plastic disk that snaps or bolts onto and covers the entire face of the wheel.^[3]
Cars with stamped steel wheels often use a full-wheel cover that conceals the entire wheel. Cars with alloy wheels or styled steel wheels generally use smaller hubcaps, sometimes called center caps.
Alternatively, a wheel cover or spare tire cover can be an accessory that covers an external rear-mounted spare tire found on some automobiles.