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Plural of Cactus
The Quick Answer
The plural of cactus is cacti or cactuses.The Plural of Cactus
The plural of cactus is cacti or cactuses.- Most cacti live in habitats subject to at least some drought.
- The great majority of cactuses have no visible leaves.

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 | ![]() ![]() |
Foreign rulings | ![]() ![]() |
some nouns adopt foreign rulings | ![]() ![]() |
Why Is There Confusion over the Plural of Cactus?
Confusion arises over the plural of cactus because its original plural form (cacti) derives from Latin and native English speakers are drawn to cactuses, which adheres to the standard ruling for forming plurals.Both cactuses and cacti are acceptable. Of note, cacti is the more common plural. (See the evidence in Google's Ngram Viewer.)
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