What Is the Plural of Criterion?
If you have ever written a business report, an email about project requirements, or a performance review, you have likely needed the word criterion. The plural of criterion is criteria. This is a direct, one-word answer: when you have more than one standard or principle by which something is judged, you use criteria. However, because criterion comes from Greek, its plural form often confuses even experienced writers. This guide will give you a clear explanation, practical examples, and the confidence to use both forms correctly in any business or everyday situation.
Quick Answer
Singular: criterion
Plural: criteria
Use criterion when referring to one single standard or rule. Use criteria when referring to two or more standards or rules. In formal writing and careful speech, criteria is always treated as a plural noun. In less formal conversation, you may hear criteria used as a singular noun, but this is not considered correct in professional or academic English.
Why This Plural Is Tricky
Many English nouns that end in -on come from Greek or Latin. Words like phenomenon (plural: phenomena) and automaton (plural: automata) follow a similar pattern. Because criteria ends in -a, it looks like a singular feminine noun in some languages, which leads to the common mistake of treating it as singular. In English, however, criteria is firmly plural.
Formal vs. Informal Use
Formal and Business Context
In formal writing—such as business proposals, academic papers, legal documents, or official reports—always use criterion for singular and criteria for plural. Using criteria as a singular noun in these contexts will be noticed and may weaken your credibility.
Formal example: The selection committee established one main criterion for the award: demonstrated leadership.
Formal example: Several criteria were used to evaluate the vendors, including cost, reliability, and delivery time.
Informal and Conversation Context
In everyday conversation, emails between colleagues, or internal team chats, you may hear people say things like, “What is the main criteria?” This is common but still considered non-standard. If you want to sound careful and professional, even in casual settings, stick to the standard forms.
Informal (acceptable but not recommended): The main criteria is price.
Better informal: The main criterion is price.
Comparison Table: Criterion vs. Criteria
| Feature | Criterion (Singular) | Criteria (Plural) |
|---|---|---|
| Number | One | Two or more |
| Verb agreement | Singular verb (e.g., is, was, has) | Plural verb (e.g., are, were, have) |
| Example | This criterion is important. | These criteria are important. |
| Common mistake | Using criteria as singular | Using criterias (not a word) |
| Formal tone | Always correct | Always correct when plural |
Natural Examples
Here are examples that show how criterion and criteria appear in real writing and speech.
Business and Workplace
- The hiring manager explained that the most important criterion for the role was five years of industry experience.
- Our team agreed on three criteria for the new software: cost, user-friendliness, and security features.
- Each proposal was judged against a single criterion: return on investment within two years.
- Before we proceed, we need to define the criteria for success in this project.
Academic and Research
- The professor stated that the main criterion for passing the course was a final grade of 70% or higher.
- Several criteria were used to select the study participants, including age, health status, and location.
Everyday Conversation
- For me, the only criterion for a good restaurant is that the food tastes fresh.
- What criteria do you use when you choose a new phone?
Common Mistakes
Even native speakers make errors with this word. Here are the most frequent mistakes and how to avoid them.
Mistake 1: Using criteria as a singular noun
Incorrect: The main criteria is customer satisfaction.
Correct: The main criterion is customer satisfaction.
Why: Criteria is plural, so it needs a plural verb (are) and cannot be described as “main” if there is only one. If you mean one standard, use criterion.
Mistake 2: Adding an -s to make criteria plural
Incorrect: We have several criterias to consider.
Correct: We have several criteria to consider.
Why: Criteria is already the plural form. Adding -s is redundant and incorrect.
Mistake 3: Using criterions
Incorrect: The report listed three criterions.
Correct: The report listed three criteria.
Why: Criterion does not form its plural by adding -s. The correct plural is criteria.
Better Alternatives and When to Use Them
Sometimes you may want to avoid the criterion/criteria confusion altogether. Here are simpler alternatives that work well in many contexts.
| Instead of | Use | When |
|---|---|---|
| criterion | standard, rule, requirement, measure, benchmark | When you want a more common word that is easier to pluralize (e.g., standards, requirements) |
| criteria | standards, guidelines, conditions, factors, specifications | In business writing, project plans, or when explaining a list of requirements |
Example with alternatives: The team defined the requirements for the new system. This is often clearer than saying “the criteria.”
Mini Practice: Criterion or Criteria?
Choose the correct word for each sentence. Answers are below.
- The main __________ for the scholarship is financial need. (criterion / criteria)
- We need to establish clear __________ before we begin the evaluation. (criterion / criteria)
- Each __________ was carefully reviewed by the committee. (criterion / criteria)
- These __________ are too vague to be useful. (criterion / criteria)
Answers:
- criterion (singular, one main standard)
- criteria (plural, more than one standard)
- criterion (singular, each one)
- criteria (plural, these refers to multiple items)
Frequently Asked Questions
1. Is it correct to say “criteria is”?
No. In standard English, criteria is plural and should be used with plural verbs like are, were, or have. Saying “criteria is” is a common error, especially in spoken English, but it is not considered correct in formal writing.
2. Can I use criterias?
No. Criterias is not a word in standard English. The plural of criterion is criteria, and no additional -s is needed.
3. What is the difference between criterion and standard?
A criterion is a specific principle or standard by which something is judged. A standard is a broader term that can mean a level of quality or a rule. In many contexts, they can be used interchangeably, but criterion often sounds more formal and precise.
4. Is criteria ever used as a singular noun in professional writing?
No. While you may encounter this usage in informal speech or some technical fields, it is not accepted in professional, academic, or formal business writing. Always treat criteria as plural to maintain accuracy and credibility.
Final Tip for Business Writers
When you are writing an email, a report, or a proposal, take a moment to check whether you are talking about one standard or several. If it is one, use criterion. If it is more than one, use criteria. This small habit will make your writing more precise and help you avoid a common grammar trap. For more guidance on similar plural forms, visit our Common Plural Forms section. If you have questions about whether a word is singular or plural, our Singular or Plural Checks page can help. For questions about this guide, please see our FAQ or contact us.
