'self-propelled' originates from the combination of 'self' and 'propel,' where 'self' refers to one's own and 'propel' means to drive or push forward.

'self-propelled' evolved from the concept of 'self' and 'propel' in the English language, combining to describe machines or vehicles that move independently.

Initially, it meant 'capable of moving by itself,' and this meaning has largely remained the same in modern usage.