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Plural of Stimulus
The Quick Answer
The plural of "stimulus" is "stimuli."The Plural of Stimulus
The plural of "stimulus" is "stimuli."- In art, stimuli are things that interests artists and give them new ideas.
- Rapid changes, called stimuli, provoke reactions in living organisms that are often very different from those expected from non-living things.
(Professor John Blamire)
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 | ![]() ![]() (Just like nucleus (plural "nuclei"), "stimulus" does not form its plural using the standard rules of English.) |
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 Stimulus?
Confusion arises over the plural of "stimulus" because its plural form ("stimuli") derives from Latin, and native English speakers are unsure whether "stimuluses," which adheres to the standard ruling for forming plurals, has come into use. Many words with Latin roots (e.g., "nucleus," "stadium," "referendum") have either adopted a standard plural ending alongside the Latin one or have dropped the Latin one entirely (e.g., "referendums"

Unlike these words, "stimuluses" is not an accepted plural. You must use "stimuli."
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