What does "shellfish" mean?

A fisheries and colloquial term for an aquatic invertebrate having an inner or outer shell, such as a mollusc or crustacean, especially when edible.

What is a synonym for "shellfish"?

Common synonyms include: bivalvia, blue point, clam, clams, cockle, cockles.

/ˈʃɛl.fɪʃ/ noun

noun ·Uncommon ·Advanced level

Noun

1
A fisheries and colloquial term for an aquatic invertebrate having an inner or outer shell, such as a mollusc or crustacean, especially when edible. countable, uncountable
2
invertebrate having a soft unsegmented body usually enclosed in a shell wordnet
3
A culinary and nutritional term for several groups of non-piscine, non-tetrapod, aquatic animals that are used as a food source. The term often exclusively refers to edible aquatic crustaceans, bivalve mollusks and cephalopod mollusks; but sometimes echinoderms may be included as well. countable, uncountable
4
meat of edible aquatic invertebrate with a shell (especially a mollusk or crustacean) wordnet

"I do not eat meat, fish, shellfish, poultry or broth."

Inherited from Middle English schellefyssch, from Old English sċielfisċ. Equivalent to shell + fish.