Are "shellfish" and "seafood" merely synonymous, or actually the same?

Question

In English, when I think of shellfish, I think of shrimps, lobsters, crabs, mussels, oysters etc., which are all "seafood" and have shells.

But there are other kinds of "seafood" such as squids and octopus that don't seem to be shellfish.

So does "seafood" refer to both or just one of the two categories of food above (or some others I haven't alluded to)? Ditto for "shellfish?"

Completely off topic, but the French call it fruits de mer, without the la. It has to do with them coming from the sea in general and not from a specific sea. — Nzall, Jun 27 '14 at 07:38
@NateKerkhofs: I deleted the "off topic" reference to French. — Tom Au, Jun 27 '14 at 13:30
shellfish means seafood that has a shell. it's in the name ... — user428517, Sep 04 '14 at 23:04

score 12 · Accepted Answer · answered Jun 27 '14 at 02:13

Actually, shellfish and seafood are not synonyms.

seafood mass noun
Shellfish and sea fish, served as food

shellfish noun (plural same)
1. An aquatic shelled mollusc (e.g. an oyster or cockle) or crustacean (e.g. a crab or shrimp), especially one that is edible
1.1 [mass noun] Shellfish as food

As you can see, shellfish are a type of seafood, but there's a rather large class of seafood that isn't shellfish, namely fish. And then there are the squid-type creatures, which are neither fish nor shellfish¹, but are seafood.

^{1 Well, actually, lots of people do consider octopus and squid to be shellfish, kind of by process of elimination: it's seafood, but it's clearly not a fish, therefore it must be shellfish.}

(Where English tends to get sloppy is with freshwater fish: many a "seafood restaurant" will have types of fish on the menu that never saw any saltwater in their life.)

score 2 · Answer 2 · answered Jun 27 '14 at 01:16

Shellfish is referring to sea creatures that have a shell, and seafood is animals that live in the sea. Shellfish is a division of seafood. In some places, there are lots of shellfish in the sea, if normal people eat lots of shellfish, not fish, they will say that. In those countries these two words are merely synonyms, but in other places they are different. It really depends where you live. If you translate shellfish to some languages, they usually mean food that have shells.

Bill, fix up your grammar. You use too much colloquialism and have some run on sentences and misuse of commas, and many other things. — Pyraminx, Dec 22 '14 at 04:12

Are "shellfish" and "seafood" merely synonymous, or actually the same?

2 Answers2