Either vs. Neither
Either and neither normally organize choices involving two alternatives. Either presents one or the other (or appears in either…or), while neither rejects both (and appears in neither…nor); negative-sentence uses of either need separate treatment.
Use either for one of two alternatives or either…or; use neither for not one and not the other, commonly with neither…nor.
Key details
Choose the right form
| Choice | Use it when | Example |
|---|---|---|
| either | one of two / either…or | Either route will work. |
| neither | not one and not the other / neither…nor | Neither route is open. |
Further guidance
Number Boundary
Both words have construction-specific agreement patterns, so verb number can depend on the structure and register.
Polarity Boundary
Either can also appear after a negative to add another negative item; do not replace every negative either with neither.
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.
- Either … or… (opens in a new tab)Cambridge Dictionary · Either…or as a two-choice construction and its contrast with neither…nor
- Neither, neither … nor and not … either (opens in a new tab)Cambridge Dictionary · Neither for negative reference to two people or things