The English language loves to keep writers on their toes. One word, two different plurals, and a whole lot of confusion—that’s the case with “appendix.” You’ve probably wondered: should I write “appendices” or “appendixes”? Are both correct? Does it depend on the context, the audience, or just personal preference?
This comprehensive guide will clear up the confusion once and for all. We’ll explore the correct plural of appendix, when to use appendices or appendixes, and how academic writing style guides like APA, MLA, and Chicago Manual of Style approach this quirky plural.
What Does “Appendix” Mean? One Word, Two Worlds
Before we dive into plural forms, let’s be clear about what an appendix actually is.
- Anatomical Appendix: A small, tube-shaped organ attached to the large intestine. (Yes, the one that can get inflamed and require surgery.)
- Textual Appendix: Supplementary text in documents, books, reports, or research papers that provides additional information.
Same word. Two very different contexts. That’s where the plural dilemma begins.
Singular and Plural Forms: Appendix, Appendices, and Appendixes
Let’s get this straight:
- Singular: Always appendix.
- Plural: Both appendices and appendixes are correct.
But here’s the catch—context matters.
- Appendices follows Latin pluralization rules.
- Appendixes aligns with modern English plural forms.
So, while both are grammatically correct, usage depends heavily on field, formality, and audience expectations.
Etymology: The Roots of “Appendix”
The word appendix comes from the Latin “appendere,” meaning “to hang upon” or “something attached.” Historically, scholars and scientists retained the Latin appendices in academic or formal contexts.
Over time, as English evolved, so did preferences. The simplified English plural appendixes gained traction, especially in non-academic, informal settings.
Thus, the debate between classical vs English plural forms continues to this day.
Appendices vs Appendixes: Clear Rules for Usage
Here’s where most writers trip up—knowing when to use appendices or appendixes. Let’s break it down.
Use Appendices When:
- Referring to supplementary text in documents, books, theses, and academic papers.
- Following scholarly conventions in formal writing.
- Adhering to an academic writing style guide like APA, MLA, or Chicago Manual of Style.
Example:
“Please refer to Appendices A and B for supporting data.”
Use Appendixes When:
- Referring to anatomical appendix in medical or biological contexts.
- Writing in informal usage, such as blogs or casual articles.
- Preferring a simplified modern English plural.
Example:
“Some patients have unusually long appendixes.”
Quick Usage Rules Table
| Context | Preferred Plural |
|---|---|
| Academic documents/theses | Appendices |
| Medical (body parts) | Appendixes |
| Informal or casual writing | Appendixes |
| Scholarly, formal writing | Appendices |
| Scientific articles (anatomy) | Appendixes |
Style Guide Preferences: APA, MLA, and Chicago Manual of Style
Different style guides have their own nuances. Here’s how they tackle the appendices vs appendixes debate:
APA Style Appendices
- The APA style appendices section prefers appendices when referencing multiple supplementary documents.
- APA suggests labeling each appendix with letters (Appendix A, Appendix B).
MLA Style Usage
- The MLA style usage leans heavily toward appendices for any textual additions at the end of papers or books.
- Consistency in labeling (Appendix A, B, etc.) is emphasized.
Chicago Manual of Style
- The Chicago Manual of Style is a strong advocate for appendices in formal, academic, and publishing contexts.
- It treats appendixes as acceptable in casual or non-academic writing but recommends appendices for scholarly work.
Real-World Examples of Appendix Usage in Sentences
Appendix (Singular Usage)
- “The appendix at the end of the book includes detailed charts.”
- “The surgeon removed her inflamed appendix successfully.”
Appendices (Plural for Books/Documents)
- “The report includes three appendices outlining case studies.”
- “Refer to Appendices B and C for statistical analysis.”
Appendixes (Plural for Anatomy)
- “Rare cases involve patients with two appendixes.”
- “Appendixes can vary in length, affecting diagnosis.”
Ambiguous Situations
What if you’re writing a casual blog post about a book’s appendix? Use appendixes for a relaxed tone, or appendices if you’re aiming for academic precision. Audience register is key.
Common Mistakes with Appendices and Appendixes
Let’s clear up the top errors:
- Mistake 1: Always using appendices, even for anatomy.
- Mistake 2: Thinking appendixes is incorrect in formal documents. It’s not wrong, but appendices is preferred.
- Mistake 3: Ignoring the language register of the audience—writing to scholars? Use appendices. Writing for casual readers? Appendixes works fine.
Regional Preference: British vs American English
- British English: Favors appendices in both academic and general contexts.
- American English: More lenient; appendixes is widely accepted in casual writing but appendices dominates in academia.
This regional preference isn’t set in stone, but it does influence usage trends in different countries.
Diagram: Which Plural to Use? A Simple Flowchart
Are you referring to a body part?
|
|-- Yes --> Appendixes
|
|-- No --> Referring to a document?
|
|-- Yes --> Appendices
|
|-- No --> Informal context?
|
|-- Yes --> Appendixes
|
|-- No --> Appendices
Audience Register and Why It Matters
Understanding your audience register is crucial. Academic readers expect precise, Latin-based plurals like appendices. Casual readers? They’re more forgiving and comfortable with appendixes.
For formal business reports or scholarly publications, aim for grammatical correctness and traditional forms. For blogs, emails, or informal guides, the modern English plural—appendixes—keeps the tone light.
FAQs: Quick Answers for Writers
Q: Can I use “appendixes” in a university paper?
A: Technically yes, but style guides like APA and MLA recommend appendices.
Q: Are “appendices” outdated?
A: Not at all. They’re still the go-to plural in academic and formal contexts.
Q: Is “appendices” British while “appendixes” is American?
A: Not strictly, but British English favors appendices more consistently.
Q: Which plural is preferred in medical journals?
A: Appendixes is commonly used for anatomical contexts.
Final Takeaway: Keep It Simple, Keep It Contextual
Here’s the golden rule:
- Use Appendices for documents, books, academic papers.
- Use Appendixes when discussing the anatomical appendix.
- Consider the formal vs. informal context and audience register to decide which fits best.
Language evolves, but clarity never goes out of style. Whether you’re writing a scientific paper, a novel, or a health blog, knowing when to use appendices or appendixes will sharpen your writing and keep your readers engage