Definition of "crossopterygian" []

• See lobe-finned fish. (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.

• "Of particular importance is the presence of the crossopterygian group, typified by Eusthenopteron foordi and Elpistostege watsoni."
• "Look at the comparison of the oldest known amphibian skeleton, Ichthyostega IK-the-o-STAY-ga, with a crossopterygian fish shown in Figure 4-8."