Tusk!

[Quino]

Hello everybody.
Quino's the name, and I'm new to this forum. I have a simple question for you: In the song "Tusk", why do they sing "tusk"? Does it have a special meaning (other than the tusks of an animal)?

Thanks in advance for your help.
/Q.

PS. I now realize that this forum isn't only for Fleetwood Mac fans (am I right?). So, to clearify, I'm adressing the song "Tusk" by Fleetwood Mac, on the album "Tusk". (A lot of tusks this...)