RE: Thagomizer

["Richard W. Travsky" <rtravsky@uwyo.edu>]

On Thu, 23 Mar 2006, Guy Leahy wrote:
> Here's the Wikipedia definition... :-)
>
> http://en.wikipedia.org/wiki/Thagomizer

It says

 It has since been adopted as a genuine anatomical term, and is used by
 multiple palaeontological authorities, including the Smithsonian
 Institution.

and gives

 http://www.nmnh.si.edu/paleo/dino/stegdcvr.htm
 ...
 Also, the spikes on the end of Stegosaurus' tail now have an official
 name, The Thagomizer, suggested in a Far Side cartoon by Gary Larson.
 (Reference: The Complete Dinosaur, James O. Farlow and M. K.
 Brett-Surman, editors, Indiana University Press, Bloomington and
 Indianapolis, Indiana, 1997, p. 302.)
 ...

How is this official? I mean, what body/agency/etc actually certifies 
this?