Hey, I want to share something that happened to me recently about parentheses or parenthesis.
I was chatting with a friend when this term suddenly popped up, and honestly, I had no idea what it meant at first.
I kept thinking, “Am I missing something here?” It was a bit confusing, and I didn’t want to reply the wrong way. So, I decided to look into parentheses or parenthesis to understand the meaning and how each one is used.
Once I figured it out, I realized how important it is to know the difference to avoid awkward moments in conversations.
Now, whenever I see parentheses or parenthesis in chats or on social media, I respond confidently without second-guessing myself.
Parentheses or Parenthesis – Quick Answer
Parenthesis is singular, referring to one set of curved brackets (), while parentheses is plural, referring to two or more sets.
Examples:
- Singular: Insert a parenthesis around the note.
- Plural: Use parentheses to add extra information.
Quick Tip: If you’re talking about one bracket, use parenthesis. For multiple, use parentheses.
The Origin of Parentheses or Parenthesis
The word parenthesis comes from Greek “parentithenai”, meaning “to put in beside”. The plural form, parentheses, follows standard English rules for Greek-derived words ending in -is.
Over time, English speakers naturally started using parentheses for general reference, while parenthesis remained a technical singular form.
This explains why people often mix them up—it’s a singular vs plural confusion rooted in history.
Focussed or Focused: Correct Spelling Explained Clearly(2026)
British English vs American English Spelling
Both American and British English use parenthesis (singular) and parentheses (plural). There is no spelling difference; the rules are consistent. The difference lies in usage style and formal writing preferences.
| Feature | American English | British English |
| Singular Form | parenthesis | parenthesis |
| Plural Form | parentheses | parentheses |
| Common Usage | Academic, business, everyday writing | Academic, formal writing |
| Preference in journalism | parentheses | parentheses |
Key Point: You don’t need to change spelling; focus on singular vs plural.
Which Spelling Should You Use?
- US audience: Use parenthesis (singular) and parentheses (plural).
- UK/Commonwealth: Same rule applies, though formal writing may prefer “parenthesis” for singular technical notes.
- Global audience: Stick to the standard singular/plural rule. Avoid mixing them in the same document.
Pro Tip: When unsure, if you refer to more than one bracket, use parentheses—it’s universally understood.
Common Mistakes with Parentheses or Parenthesis
- Using parentheses as singular:
❌ Insert a parentheses here.
✅ Insert a parenthesis here. - Confusing plural and singular in lists:
❌ Add parenthesis around each point.
✅ Add parentheses around each point. - Overusing parentheses in formal writing—replace with commas or dashes for clarity.
Parentheses or Parenthesis in Everyday Examples
- Email: Please review the document (see section 3).
- News article: The CEO announced a new policy (effective next month).
- Social media: I love pizza (especially pepperoni)!
- Formal writing: The term “quantum entanglement” (Einstein, 1935) is widely studied.
Tip: Parentheses add extra information without breaking sentence flow.
Parentheses or Parenthesis – Google Trends & Usage Data
Search trends show that “parentheses” is far more commonly used than “parenthesis”, reflecting everyday usage in multiple contexts.
Popular regions: United States, UK, Canada, Australia.
Usage context: Writing guides, grammar queries, educational resources.
| Keyword Variation | Average Monthly Searches | Popular Countries |
| parenthesis | 2,900 | US, UK |
| parentheses | 18,000 | US, UK, Canada, Australia |
FAQs
1. Can I use parentheses instead of parenthesis?
Yes, if you are referring to more than one bracket. For a single bracket, use parenthesis.
2. Are parentheses used in math?
Yes, both singular and plural forms are used to indicate grouping of numbers or operations.
3. Is parenthesis American or British English?
It’s standard in both, with no spelling difference. Only singular vs plural matters.
4. Can parentheses be inside parentheses?
Yes, though nested parentheses are usually discouraged in formal writing. Use brackets [ ] instead.
5. How do I punctuate sentences with parentheses?
Place punctuation outside unless the parenthetical is a complete sentence.
6. Why do people get parenthesis and parentheses confused?
Because the plural form ends in -es, it’s easy to mix up singular vs plural.
7. Are parentheses necessary in writing?
Not always; they are optional but useful for adding extra information without breaking flow.
Conclusion
Understanding the difference between parenthesis and parentheses helps you write accurately and professionally. Parenthesis is singular, parentheses is plural, and both are used the same way in American and British English. Avoid common mistakes by remembering the singular/plural rule, and use them effectively in emails, articles, social media, and formal writing. While parentheses dominates in everyday searches, knowing the correct usage of parenthesis will give your writing clarity and precision. When in doubt, count your brackets: one is parenthesis, two or more are parentheses. Correct usage enhances readability and ensures your writing is both grammatically correct and stylistically polished.
I’m Samantha Greene, working at Englaora.com to explain language differences and provide readers with easy-to-understand insights on commonly mistaken terms.
