Plural of Tooth
The plural of “tooth” is “teeth.” It is an irregular plural, so ordinary countable uses do not form the plural by adding -s.
The plural of “tooth” is “teeth,” not “tooths.”
Key details
Choose the right form
| Meaning / situation | Form / construction | Decision |
|---|---|---|
| one tooth | tooth | Use the singular form. |
| more than one tooth | teeth | Use the irregular plural. |
| attempted regular plural | tooths | Do not use this as the ordinary plural of the anatomical noun. |
Quick tests
Meaning / construction test
Are you referring to more than one “tooth”?
If yes: Use the irregular plural “teeth.”
If no: Use “tooth” for one.
Examples
The model shows one tooth.
A single item takes “tooth.”
The model shows several teeth.
The ordinary plural of “tooth” is “teeth.”
The chart labels the teeth by position.
The irregular plural remains “teeth.”
Further guidance
Core difference
“Tooth” is singular; “teeth” is its irregular plural.
Fast Test
Use “one tooth” but “two teeth,” “several teeth,” and plural verb agreement where required.
Usage Boundary
Do not form the ordinary plural as “tooths.” Specialized compounds may contain “tooth” attributively, but that does not change the noun’s plural.
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- tooth — Cambridge Dictionary (opens in a new tab)Cambridge University Press · Direct dictionary evidence that the plural of tooth is teeth.