We use words that begin with the prefixes dis and un every day: Perhaps you’ve told someone you’re disappointed or unconvinced or that your new shoes are uncomfortable. How do these letters change the meaning of a word?
To begin with, there are slight differences between the prefixes dis and un: Dis means “not” or “the opposite of” and is sometimes attached to the beginning of verbs to indicate the undoing of an action. Un can also mean “not,” depending on the base word, but can also mean “deprived of” or “to release.”
Here, we’ll dive into the differences between these two common prefixes and provide examples of how to use them in your writing.
When should you use the prefix dis?
Dis is a prefix added to the beginning of base words that means “not” or “opposite of”; it can also be attached to verbs to show the undoing of an action. The word disappear consists of the prefix dis and the verb appear, so its literal definition is “to not appear” or “doing the opposite of appearing.”
Words with dis are known as negatives, which are words that show that something is untrue, nullified, or not happening.
There are times when dis may seem like the best prefix to use, but that might not always be the case. Take disorganized and unorganized: Both words indicate that someone or something is not organized, but their implications are quite different.
Someone who is described as disorganized is not only not organized—they may also be considered messy. The word unorganized simply means “the lack of organization.”
Take similar care when choosing between dis and de. The negative prefix de, like dis, is attached to the beginning of verbs to show the undoing of an action, but it has a different meaning than dis depending on which base word is used.
We’ll use the word compose as an example. When we say something decomposed, we mean it disintegrated, rotted, or separated into individual parts. In contrast, discomposed means “to disturb” or “to destroy.”
When should you use the prefix un?
Attach the negative prefix un to the beginning of a base word to change its meaning to “not,” “deprived of,” or “released from.”
Like words with dis, words with un are also known as negatives—words added to show that something is untrue, nullified, or not happening.
Since un and dis both mean “not,” you might think that they’re interchangeable in cases like uninterested and disinterested, but there are rules on when to use them. When someone says they’re uninterested in something, they usually mean they have no interest in learning more about something; someone who is disinterested in something is impartial or unbiased.
Someone who is uninterested in sports very rarely watches sports, whereas someone who is disinterested in sports may watch sports but not root for a particular team.
That said, some people still use them interchangeably, and they’re not technically wrong for doing so.
Un is also used with words that have suffixes—letters or groups of letters added to the end of a base word to create a new word. When this is done, the resulting word is an adjective.
Here’s an example: The word unstabilized consists of the prefix un, meaning “not”; the verb stabilize, meaning “to make steady”; and the suffix –ed. The resulting word is an adjective that means “not steady” or “not stable.”
30 commonly used words with the prefix dis
30 commonly used words with the prefix un
8 examples of using dis and un in a sentence
Here are four examples of how to use the prefix dis in a sentence:
- My brother’s room was so disorganized it was hard to find the floor.
- My research partner took a disinterested approach to the experiment.
- The surgery left him in some discomfort, which lasted for two days.
- Antonio leaves negative restaurant reviews when he’s dissatisfied with the service.
Here are four examples of how to use the prefix un in a sentence:
- Kate didn’t realize how unhappy she was until she left her partner.
- The crack left the merry-go-round very unstable.
- It took the barber ten minutes to untangle her client’s hair.
- These shoes are so tight that I can’t wait to untie the laces.
How to use dis and un FAQs
When should you use dis?
Use dis as a negative prefix to change the meaning of the word to “not something” or “the opposite of something.” It can also be attached to the beginning of verbs to represent the undoing of an action.
When should you use un?
Use un as a negative prefix to mean “not something,” “released from something,” or “deprived of something.” When paired with a suffix such as -ed or -able, the resulting word is an adjective—unstabilized, for example.
What are examples of common words using un and dis?
Some common words using un and dis are unorganized and disorganized, unsatisfied and dissatisfied, and uninterested and disinterested.