While I was flipping through a copy of Wendy Johnson's Socks from the Toe Up at a local yarn store yesterday a word I wasn't familiar with caught my eye: trilobite. The word first appeared in the title of one of the patterns (Trilobite Socks) and later in a description of the genesis of a second pattern (Sheri's Posies Socks).
Apparently triobites are a well-known (just not to me!) group of extinct marine arthropods that form the class Trilobita frequently found as fossils.
This Guide to the Orders of Trilobites seems like a good place to learn more, especially since it is maintained by a biologist.