The word swastika is derived from the Sanskrit root swasti, which is composed of su 'good, well' and asti 'is; it is; there is'.
With well-being (swasti) we would follow along our path, like the Sun and the Moon. May we meet up with one who gives in return, who does not smite (harm), with one who knows. — The Rigveda V.51.15
Didn't know that the symbol spread far and wide. That's some very interesting history (minus the Nazis).