Dilate vs Dialate Quiz: Test Yourself
Five quick questions on dilate vs dialate. Pick an answer to get instant feedback.
Flip Cards: Quick Review
Hover over a card, or tap it on mobile, to see the meaning.
To make or become wider or larger.
“The eye drops made her pupils dilate.”
Not a real word.
It is a misspelling. Write “dilate” instead.
The act of widening or expanding.
“Pupil dilation is a normal response to low light.”
To turn a dial or call a phone number.
“Please dial 9 for an outside line.”
People mix up dilate vs dialate because of how the word sounds. We say it “dy-LATE,” and the “dy” sound is easy to spell with “dia,” as in “dial” or “diameter.” Only one spelling is correct, and it is “dilate.”
| Term | Meaning | Part of speech / Category | Example sentence |
|---|---|---|---|
| Dilate | To make or become wider, larger or more open | Verb / correct spelling | Blood vessels dilate when the body needs to cool down. |
| Dialate | None; a misspelling of dilate | Not a word / common error | Incorrect: Her pupils dialated in the dark. |
| Dilation | The act or state of widening or expanding | Noun / correct spelling | Dilation of the pupils is a normal response to dim light. |
| Dial | To turn a dial, or to call a number on a phone | Verb and noun / different word | He dialed the number twice. |
What does dilate mean?
Dilate means to make or become wider, larger or more open. It is a verb, and its forms are dilates, dilated and dilating.
You will see it most often in medicine and science. Pupils dilate in dim light, blood vessels dilate to increase blood flow, and airways can dilate to make breathing easier. In physics, “time dilation” describes how time can stretch under certain conditions. The word comes from the Latin dilatare, meaning to widen.
Dilate has a second, more formal meaning: to speak or write at length about something, usually with the word “on,” as in “She dilated on the history of the town.” This sense is less common today.
Is “dialate” a real word?
No, “dialate” is not a standard English word. It is a misspelling of “dilate,” and spell-checkers will flag it.
The mistake is understandable. Many English words begin with “dia,” such as dial, diagram, dialogue and diameter, so the brain fills in an “a” that does not belong. The correct spelling has no “a” at all: d-i-l-a-t-e.
Dilate vs dialate: why do people confuse them?
The confusion comes from pronunciation and from similar-looking words. Dilate is pronounced “dy-LATE,” and the first syllable sounds just like the start of “dial” and “diagonal.” Writers spell what they hear, and “dia” feels right for that sound.
Another factor is that the word is mostly encountered in speech, such as at a doctor’s office, rather than in writing. Because few people see it spelled out often, the wrong version sticks.
How can you remember how to spell dilate?
Remember that dilate has no “a,” just like the word “wide.” Break it into two parts, “di” plus “late,” and you will have the correct spelling every time.
Common mistakes with dilate vs dialate
- ✗ The doctor said my pupils would dialate.
✓ The doctor said my pupils would dilate. - ✗ Her eyes dialated in the dark.
✓ Her eyes dilated in the dark. - ✗ Pupil dialation is normal in dim light.
✓ Pupil dilation is normal in dim light. - ✗ Blood vessels dialate when you exercise.
✓ Blood vessels dilate when you exercise. - ✗ Please dilate the number on your phone.
✓ Please dial the number on your phone.
Memory tricks
- No “a” in wide. Dilate means to widen, and neither “wide” nor “dilate” has an “a” in the middle.
- Split it: di + late. Say it as two parts and spell exactly what you see.
- Dial is for phones. If you are calling someone, use “dial.” If something is getting wider, use “dilate.”
Frequently asked questions
Is it dilate or dialate?
The correct spelling is dilate. Dialate is a common misspelling and is not found in standard dictionaries.
Is dialate ever correct?
No. Dialate is not an accepted spelling in any standard form of English. Always write dilate.
What is the past tense of dilate?
The past tense is dilated, as in “Her pupils dilated in the dark.” The present participle is dilating.
What is the noun form of dilate?
The noun form is dilation, as in “pupil dilation.” Dialation is a misspelling.
What does it mean when your pupils dilate?
It means your pupils are getting larger. This is a normal response to low light, and it can also happen with strong emotion or after certain eye drops.
Conclusion
When it comes to dilate vs dialate, only dilate is correct. Remember that there is no “a” in it, just like in “wide.” Share this with someone who mixes these two up.