Definition of "eurypterid" [eurypterid]

• Any of various large, segmented aquatic arthropods of the order Eurypterida that existed from the Ordovician Period to the Permian Period. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "My favorite is his drawing of a eurypterid / sea scorpion."
• "This paper, with Hünicken as a coauthor, revises the identity of this fossil as a “bizarre eurypterid”, a water scorpion Eurypterida."
• "What all this summons into my mind, as I continue the path of free association from T.S. Eliot through my eurypterid to Rhyniognatha, is H.P. Lovecraft's splendid novella, "At the Mountains of Madness" (1936), one of his few genuine science-fiction stories, and a dazzling one."