Definition of aspiration. 1  1a : a strong desire to achieve something high or great an aspiration to become famous âusually plural a young man with political/literary aspirationsb : an object of such desire An acting career is her aspiration.
Wheel and axle. The wheel and axle is one of six simple machines identified by Renaissance scientists drawing from Greek texts on technology. The wheel and axle consists of a wheel attached to a smaller axle so that these two parts rotate together in which a force is transferred from one to the other.
The hub is the center of the wheel, and typically houses a bearing, and is where the spokes meet. A hubless wheel (also known as a rim-rider or centerless wheel) is a type of wheel with no center hub. More specifically, the hub is actually almost as big as the wheel itself.