Criterion Plural Form: Rule, Examples, and Mistakes

If you are looking for the plural of criterion, the direct answer is criteria. This is not a standard English plural that simply adds an -s or -es. Instead, criterion follows a Greek plural pattern, and using it correctly in writing, email, or conversation can be tricky. This guide explains the rule, shows you natural examples, highlights common mistakes, and gives you a quick way to check yourself.

Quick Answer: What Is the Plural of Criterion?

Singular: criterion
Plural: criteria

You use criterion when talking about one standard or principle. You use criteria when talking about two or more standards or principles. In formal writing and careful speech, criteria is always plural. In everyday conversation, some speakers treat criteria as a singular noun, but this is widely considered a mistake in professional and academic contexts.

Why Does Criterion Have an Irregular Plural?

English borrowed criterion directly from Greek, where it already had a specific singular and plural form. Many Greek-derived words in English keep their original plural endings. For example:

• Phenomenon → phenomena
• Stimulus → stimuli
• Criterion → criteria

Because of this origin, you cannot simply add -s to make the plural. Knowing this pattern helps you avoid a very common error.

Formal vs. Informal Use: When to Be Careful

Formal Writing and Professional Email

In academic papers, business reports, job applications, and formal emails, you must use criteria as a plural noun. Using it as a singular will look unprofessional. For example:

• Correct (formal): The selection criteria are clearly defined.
• Incorrect (formal): The selection criteria is clearly defined.

If you need a singular form in formal writing, always use criterion.

Everyday Conversation and Informal Email

In casual conversation, you will sometimes hear people say, “The main criteria is…” This is common but still considered non-standard. If you are learning English for professional or academic purposes, it is safer to keep the distinction. In very informal chat, some native speakers use criteria as a singular, but you should avoid it in your own writing until you are sure of the context.

Comparison Table: Criterion vs. Criteria

Natural Examples: Criterion and Criteria in Real Sentences

Here are examples that show how these words appear in real writing, email, and conversation.

Using Criterion (Singular)

• Academic: The only criterion for admission is a minimum GPA of 3.0.
• Business email: Please note that delivery time is a key criterion in our supplier evaluation.
• Conversation: “What’s your main criterion for choosing a hotel?” “Cleanliness, definitely.”

Using Criteria (Plural)

• Academic: The criteria for this assignment include clarity, originality, and proper citation.
• Business email: We have updated the selection criteria to reflect new market conditions.
• Conversation: “What criteria do you use when hiring?” “Experience, attitude, and teamwork.”

Common Mistakes with Criterion and Criteria

Even advanced English learners make these errors. Here are the most frequent ones and how to fix them.

Mistake 1: Using Criteria as a Singular Noun

Incorrect: This criteria is not fair.
Correct: This criterion is not fair. OR These criteria are not fair.

Why it happens: Criteria ends with -a, which sounds like a singular ending to many learners. In reality, it is the plural form.

Mistake 2: Adding an -s to Criterion

Incorrect: We have several criterions to meet.
Correct: We have several criteria to meet.

Why it happens: Most English nouns add -s or -es for the plural. Criterion is an exception.

Mistake 3: Using Criterion When You Mean Multiple Standards

Incorrect: The criterion for the job include a degree and five years of experience.
Correct: The criteria for the job include a degree and five years of experience.

Why it happens: The speaker knows the word criterion but forgets to switch to the plural form when listing more than one standard.

Better Alternatives: When to Use a Different Word

Sometimes you can avoid the confusion entirely by using a simpler word. This is especially helpful in everyday conversation or informal email.

• Instead of: What are the criteria?
  Use: What are the requirements?
• Instead of: The main criterion is price.
  Use: The main factor is price.
• Instead of: We need to meet these criteria.
  Use: We need to meet these standards.

Using requirements, factors, or standards is perfectly acceptable in most contexts and removes the risk of a grammar error. However, in formal academic or technical writing, criterion and criteria are often the precise terms expected.

Mini Practice: Test Your Understanding

Choose the correct word (criterion or criteria) for each sentence. Answers are below.

1. The main __________ for this scholarship is financial need.
2. We have established three __________ for evaluating performance.
3. Each __________ must be met before we proceed.
4. All __________ have been reviewed by the committee.

Answers:

1. criterion (singular – one main standard)
2. criteria (plural – three standards)
3. criterion (singular – each individual standard)
4. criteria (plural – all standards)

FAQ: Common Questions About Criterion Plural

1. Is it ever correct to say “criterias”?

No. Criterias is not a standard English word. The correct plural is criteria. Adding an extra -s is a common mistake.

2. Can I use “criteria” with a singular verb in informal English?

Some native speakers do this in casual conversation, but it is not considered correct in formal writing or professional communication. To be safe, always use a plural verb with criteria.

3. What is the singular of “criteria”?

The singular is criterion. If you need to refer to one standard, use criterion. If you are unsure, ask yourself: “Is this one thing or more than one?”

4. Are there other words like “criterion” that follow the same pattern?

Yes. Common examples include phenomenon (plural phenomena), datum (plural data), and medium (plural media). However, note that data is now often used as a singular mass noun in informal contexts, while criteria is still expected to be plural in careful use.

Final Tip for Real Writing and Conversation

When you write an email or a report, take a moment to check whether you need the singular or plural form. If you are talking about one standard, use criterion. If you are talking about two or more, use criteria. This small habit will make your English sound more precise and professional. For more help with similar tricky plurals, explore our Plural Spelling Rules section or visit FAQ for common questions.