the origins of the clan cain or cian

[racsfpd6595]

the origins of the clan cain or the clan cian

[hiorta]

'Clan' is a corruption of 'Clann' (clown) the gaidhlig word for children.

[Cadbren]

You might find this interesting.

Clan McCain - Home Page

You'd need to be more specific about your name is from though as the above site posits two different origins for that name and yours may not even be related to them.

Also this.
Clann Mhic Eain ....Clan McCain

You might also consider that your Cain is a sept of another clan rather than a clan unto itself.