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Plural of Jellyfish
The Quick Answer
The plural of jellyfish is jellyfish or jellyfishes.(If you're talking about the number of jellyfish (possibly of the same type), use jellyfish. If you're talking about the number of different types, use jellyfishes.)
The Plural of Jellyfish
The first thing to note about jellyfish is that it is one word, not two. Forming the plural of jellyfish follows the same rules as for fish, which can be fish or fishes. Similarly, the plural of jellyfish is jellyfish or jellyfishes.- There are five jellyfish in the tank.
- The aquarium has five jellyfishes at the moment.

Are You Good at Plurals?
Here's a quick test.The Standard Rules for Forming the Plurals
The table below shows the standard rules for forming the plurals of nouns in English.Type | Example of Type | Forming the Plural | Plural |
---|---|---|---|
Most Nouns | ![]() ![]() |
add s | ![]() ![]() |
Noun Ending s, sh, ch, x or z | ![]() ![]() |
add es | ![]() ![]() |
Nouns ending [consonant] o | ![]() ![]() ![]() |
add either s or es (There are no rules for this - you have to know.) |
![]() ![]() ![]() |
Nouns ending [vowel] o | ![]() ![]() |
add s | ![]() ![]() |
Nouns ending [consonant] y | ![]() ![]() |
change the y to an i and add es | ![]() ![]() |
Nouns ending [vowel] y | ![]() ![]() ![]() |
add s | ![]() ![]() |
Nouns ending f or fe | ![]() ![]() |
ves and/or s (There are no rules - you have to know.) |
![]() ![]() |
Exceptions | ![]() ![]() |
some nouns undergo a vowel or letters change | ![]() ![]() |
More exceptions | ![]() ![]() |
some nouns do not change at all | ![]() ![]() |
Why Is There Confusion over the Plural of Jellyfish?
Confusion arises because people encounter both jellyfish and jellyfishes but fail to recognize the context in which each word is used. Remember that it is the same as for fish.
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