Fountain and Mainspring

Fountain noun - A point or place at which something is invented or provided.

Mainspring is a synonym for fountain in source topic. In some cases you can use "Mainspring" instead a noun "Fountain".

Nearby Word: fount

Mainspring noun - The most important spring in a mechanical device (especially a clock or watch); as it uncoils it drives the mechanism.

Fountain is a synonym for mainspring in motive topic. You can use "Fountain" instead a noun "Mainspring", if it concerns topics such as origin, base, cause.