Antiarcha

plural noun

An·​ti·​ar·​cha

: a subclass or other division of Placodermi comprising small Devonian freshwater ostracoderms having complex bony armor on the anterior part of the body and a pair of pectoral appendages resembling paddles

Word History

Etymology

New Latin, from anti- entry 1 + -archa (from Greek archos anus); from the contrast in the location of the anus with that of the Urochordata

The Ultimate Dictionary Awaits

Expand your vocabulary and dive deeper into language with Merriam-Webster Unabridged.

1. Expanded definitions
2. Detailed etymologies
3. Advanced search tools
4. All ad-free

Discover what makes Merriam-Webster Unabridged the essential choice for true word lovers.

Start Your Free Trial Now