Fish or Fishes?

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What Is the Difference between "Fish" and "Fishes"?

"Fish" and "fishes" are easy to confuse because the rules on which to use are not simple.

• Fish. "Fish" is by far the most common plural of "fish," but "fishes" is also acceptable.
• I have three fish in my tank: Barney, Bob, and Brian.
• I have three fishes in my tank: Barney, Bob, and Brian.
(This is acceptable, but it is rarer.)
• Fishes. "Fishes" is an acceptable plural, but it is rare in everyday language. The word "fishes" is most commonly used by marine biologists to mean "different species of fish." In other words, "fishes" best translates as "different types of fish."
• I have three fishes in my tank: goldfish, guppies, and neon tetras.
(Here, "fishes" means types of fish. There may be dozens of fish.)

Fish

Here are some examples with the word "fish":

• A pike is a predatory fish.
(Here, "fish" is singular.)
• I caught three fish in the river yesterday – all pike.
(In this example, "fish" is plural.)
• I caught three fish in the river yesterday – two pike and a perch.
(In this example, there are different species of fish, but "fish" is still the most common plural.)

Fishes

Here are some examples with the word "fishes":

• I caught three fishes in the river yesterday – all pike.
("Fishes" has been used as the plural. This is acceptable but rare. "Fish" would be more common.)
• I caught three fishes in the river yesterday – two pike and a perch.
(This is acceptable but rare. "Fish" would be more common. It doesn't matter that there is more than one species of fish.)
• There are several fishes in this river, including pike and perch.
(This is something a biologist would say. Remember that, when used by biologists, "fishes" best translates as "different types of fish" or "species of fish.")

Now look at this example:

• I caught two fishes in the river yesterday – five pike and six perch.
(This is something a biologist might say.)

Here are some real-life examples:

• Fishes live in the sea, as men do on land; the great ones eat up the little ones. (Playwright William Shakespeare)
(Here, Shakespeare has used "fishes" as the plural of fish. This is acceptable but rare.)
• Ichthyology is the study of fishes.
(This is something a biologist would say. The plural "fishes" describes multiple species of fish.)

A Video Summary

Here is a 3-minute video summarizing when to use "fish" and "fishes."

Are you a visual learner? Do you prefer video to text? Here is a list of all our grammar videos.

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