What’s the Plural of Syllabus: Understanding Academic Terminology

Syllabus, Syllabi, Syllabuses — See the Pattern

The word syllabus comes from Latin. That is why it has two plural forms. Look at these examples:

• The teacher handed out the syllabus on the first day. (one course = singular)
• All the syllabi for this term are online. (many courses = plural)
• The school updated its syllabuses last year. (many courses = plural)
• Have you read the syllabus for your history class? (one class = singular)

Did you see the pattern? When there is one, you say syllabus. When there are two or more, you can say syllabi or syllabuses.

When to Use Syllabi and When to Use Syllabuses

Both forms are correct, but they are used in slightly different ways.

Use “syllabi” when:

• You are writing for school or university
• You want to sound more formal or academic
• You see it used in textbooks or official documents

Use “syllabuses” when:

• You are writing in everyday English
• You want to follow the normal English rule (add -es)
• You are not sure which one to pick — syllabuses is always safe

Easy way to remember: Syllabus ends in -us. For the Latin plural, change -us to -i and get syllabi. For the English plural, add -es and get syllabuses. Both are right.

Real-Life Examples With Syllabus, Syllabi, and Syllabuses

• Please read the syllabus before the first class. (the course plan for one class)
• The professors shared their syllabi at the start of the term. (course plans for many classes)
• I need to compare the syllabuses for both English courses. (plans for two courses)
• The syllabus says the exam is in week ten. (the plan for one course)
• The department reviewed all the syllabi before the new year started. (many course plans)

You are doing great. Now let us look at the mistakes many learners make.

The Most Common Mistakes With the Plural of Syllabus

Even native speakers are not sure about this one sometimes — so if you have mixed up the forms before, you are not alone. Latin plurals do not follow normal English rules, and that confuses many people.

Mistake 1: Writing “syllabus’s” as a plural

How to remember: An apostrophe (‘) shows who owns something. “The syllabus’s due date” means the due date of the syllabus. But syllabi or syllabuses without an apostrophe is the plural — it means more than one syllabus.

Mistake 2: Using “syllabus” when you need the plural

How to remember: If there is a number before it (two, three, five, many), you need the plural: syllabi or syllabuses.

Mistake 3: Writing “syllabusses” with a double S

How to remember: Just add -es to the end. Do not double the S. Syllabus + es = syllabuses.

Other words that follow this same Latin pattern: focus → foci, radius → radii, fungus → fungi, cactus → cacti, nucleus → nuclei.

Test Yourself: Syllabus, Syllabi, or Syllabuses?

Choose the correct answer for each sentence. Click Check to see if you are right.

Keep Going — You Are Building Something

You just learned the plural of syllabus. That is one more Latin plural you will never get wrong again.

Syllabus becomes syllabi because it follows the Latin -us to -i rule. The word focus follows the exact same pattern — but do you know what its plural is? Is it focuses or foci? And when should you use each one?

Next lesson: What’s the Plural of Focus?

Sources

Definition of syllabus.

Origin of syllabus.