Thanks all, this is great! I would love to hear more stories of where various clans got their name. As I suspected, this is a really interesting and varied topic.

Is it correct to say that traditionally, official clans were formed by royal charter? I wonder if the clan name was typically part of the charter?

What about today? Is it correct that there are no longer royal clan charters? Still, I assume that there is an official way to register a clan (and its name and who the chief is and such). Is this done by the college of heralds through the Lord Lyon?