Grammar 101: Defuse vs. Diffuse


We often learn phrases by ear before we learn to write them. So, it’s very common for someone to use the incorrect word as many words sound the same but are spelt differently and differ in meaning.

This month, let’s look at “Defuse” and “Diffuse”, two words that are often misused.

Defuse vs. Diffuse examined and defined for you


A word or phrase that describes an action, condition, or experience.

A word or phrase that describes an action, condition, or experience.



A word that describes a person, place, thing, event, substance or quality.

(a) To prevent a bomb from exploding.
(b) To make a difficult or dangerous situation calmer by reducing or removing its cause.


(a) To (cause something to) spread in many directions.
(b) To (cause a gas or liquid to) spread through or into a surrounding substance by mixing with it.


(a) Spread out and not directed in one place.
(b) Disapproving - not clear or easy to understand.

Deactivate, cripple, lessen, moderate, pacify, soften, restrain, weaken, alleviate.

Verb: Broadcast, circulated, diluted, dispersed, expanded, extended, separated, strewn, radiated.

Adjective: Wordy, longwinded, rambling, verbose, talkative.

He managed to defuse the bomb in the nick of time.

Chris defused the tense situation by cracking a joke.

My teacher acted fast to successfully defuse the situation in class.

He is nervous as this will be his first time defusing a bomb.

The police were called in to defuse threats of a violent riot.

In his photography class, Robert learnt how to use a screen to diffuse light.

The gas from the factory diffused throughout the park.

I am loving the heat that is diffusing from the radiator on this cold winter day.

The loud bang diffused the crowd at the entrance.

Sally was well known for her diffuse literary style.

Reference: Cambridge Dictionary

Now that you understand the words and know how to use it in a sentence, take our 10-question quiz to test your knowledge.

Scroll down for answers


1. After cultivating the land, the farmer _____ (diffused, defused) the seeds all of it.

2. I felt much better once the air conditioner _____ (diffused, defused) cool air around the living room.

3. My teacher _____ (diffused, defused) some tension by letting students take turns sharing their opinions on the incident.

4. We wasted too much time as now, I only have minutes to _____ (diffuse, defuse) the bomb.

5. Paul offered to resign to _____ (diffuse, defuse) the crisis in the office.

6. The Australian envoy looks to _____ (diffuse, defuse) trade tensions as conflict looms.

7. I hung the air freshener in the car and turned on the car’s air conditioner to help _____ (diffuse, defuse) the fragrance.

8. The talk on the benefits of free trade was painfully _____ (diffused, defused).

9. We believe that _____ (diffused, defused) light can increase the production of tomatoes by up to 10%.

10. The police officers successfully _____ (diffused, defused) a dangerous situation without harm this weekend.


1. diffused; 2. diffused; 3. defused; 4. defuse; 5. defuse; 6. defuse; 7. diffuse; 8. diffused; 9. diffused; 10. defused

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