Meaning & use
dilate
Last updated
Meanings
verbintransitive
To become wider or more open.
Grammar: No object: her pupils dilated.
Patterns
- dilate in something
Your pupils dilate in the dark.
Blood vessels dilate when you are hot.
The cervix dilates during labor.
verbtransitive
To make something wider or more open.
Grammar: Takes an object: the drops dilate the pupils.
Patterns
- dilate something
The doctor used drops to dilate my eyes.
Some medicines dilate the airways.
Heat can dilate small blood vessels.
verbintransitiveformalold-fashioned
To speak or write at length about a subject.
Grammar: Followed by on: dilate on a topic.
Patterns
- dilate on something
He dilated on the history of the village for an hour.
She did not wish to dilate on the subject.
The speaker dilated at length on his travels.
Word forms
| third person singular | dilates |
|---|---|
| past tense | dilated |
| past participle | dilated |
| -ing form | dilating |
Common combinations
- pupils dilate
- Pupils dilate in dim light.
- blood vessels dilate
- Blood vessels dilate to release heat.
- fully dilated
- The cervix was fully dilated.
- dilate the eyes
- The optician will dilate your eyes.
- dilated pupils
- Dilated pupils can signal fear.
Synonyms and how they differ
- widen
- An everyday word for becoming wider in any context.
- expand
- Means growing larger in all directions.
- enlarge
- Means making bigger, usually something made by people.
- open up
- Informal wording for becoming open.
Opposites
Word family
Commonly confused: dilate or dilute?
dilate vs dilute
Dilute means to make a liquid weaker by adding water; it is not about widening.
Practice
In dim light the pupils of your eyes ___ to let in more light.
Choose one answer.
Pupils widen, or dilate. Dilute is for liquids and the other words do not fit.
Make it your own
Write a sentence using “dilate”, then check it and compare it with the examples above.