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

These tiny dark-yellowish mollusks, native to rivers in China and Southeast Asia, have already wreaked havoc in South America, and for years have kept officials and ecologists across the United States on high alert. —Rosanna Xia, Los Angeles Times, 2 Nov. 2024

It’s long been believed that the first of these animals sported a single, simple shell—but a new fossil, described this week in Science, suggests early mollusks were flat slugs with spiny armor instead. —Molly Herring, science.org, 2 Aug. 2024

For example, arthropods, mollusks, and chordates appeared during this period. —Scott Travers, Forbes, 8 Sep. 2024

Assembling genomes for octopuses, squid and other mollusks has been a serious technical challenge until recently, explains Rebekah Rogers, a genome biologist at the University of North Carolina at Charlotte, who was not involved in the study. —Viviane Callier, Scientific American, 3 Sep. 2024

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

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-