mollusk

noun

mol·​lusk ˈmä-ləsk 

variants or mollusc

: any of a large phylum (Mollusca) of invertebrate animals (such as snails, clams, or squids) with a soft unsegmented body usually enclosed in a calcareous shell

broadly : shellfish

molluscan adjective

or less commonly molluskan

mə-ˈlə-skən 

mä-

Examples of mollusk in a Sentence

Recent Examples on the Web

The ingredient, a glycoprotein found in these mollusks’ sticky mucus, has become a popular addition to skincare products over the years. —Hunter Boyce, AJC.com, 13 Jan. 2026

Natural pearls develop organically when a tiny grain of sand becomes trapped inside a mollusk. —Elle Meier, InStyle, 9 Jan. 2026

The mollusks and equipment were valued at nearly $20,000. —Ben Brasch, Washington Post, 1 Jan. 2026

Most of the organisms were marine bristle worms, crustaceans, and mollusks such as snails and mussels. —Bojan Stojkovski, Interesting Engineering, 7 Dec. 2025

Word History

Etymology

French mollusque, from New Latin Mollusca, from Latin, neuter plural of molluscus thin-shelled (of a nut), from mollis

First Known Use

1783, in the meaning defined above

Rhymes for mollusk

• mollusc

Kids Definition

mollusk

noun

mol·​lusk

variants or mollusc

ˈmäl-əsk 

: any of a large phylum of invertebrate animals (as snails, clams, and octopuses) with a soft body lacking segments and usually enclosed in a shell containing calcium

molluscan adjective

also molluskan

mə-ˈləs-kən 

mä-

Medical Definition

mollusk

noun

mol·​lusk

variants or mollusc

ˈmäl-əsk 

: any invertebrate animal of the phylum Mollusca

molluscan adjective

also molluskan

mə-ˈles-kən, mä-