plural noun

: a class of Mollusca including the clams, oysters, and mussels, having the body bilaterally symmetrical, compressed, and more or less completely enclosed within the mantle that secretes a bivalved shell whose right and left parts are connected by a hinge over the animal's back, having no distinct head, usually two lamelliform gills on each side of the body, and the ventral region differentiated in most of the forms into a muscular plowshare or tongue-shaped foot by means of which the animal burrows or moves about, and having the posterior margins of the mantle lobes drawn out in the burrowing species into tubes through which water passes into and out of the mantle cavity
adjective or noun

Word History


New Latin, from lamell- + -branchia

Love words?

You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

  • More than 250,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!

Dictionary Entries Near Lamellibranchia

Cite this Entry

“Lamellibranchia.” Dictionary, Merriam-Webster, Accessed 12 Apr. 2024.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!