To defuse something is to make it safer or less tense. To diffuse something is to spread it out. A calm explanation can defuse an argument. Frosted glass can diffuse light.
Defuse a tense situation
“The manager defused the argument by listening to each person in turn.” The discussion became less heated. The literal sense is to remove a fuse. In everyday writing, defuse often describes easing a conflict.
Diffuse light or describe it as diffuse
“The frosted glass diffused the light from the lamp.” Here diffuse is a verb. “A diffuse glow filled the hall” uses it as an adjective meaning spread out or without a sharp focus.
Which result do you mean?
If a remark eased tension in a room, write that it defused the situation. If the scent of coffee spread through the room, write that it diffused through the air.
Try it
“An apology helped ___ the tension. The scent of coffee began to ___ through the room.”
Show the answer
Use defuse for tension that eases and diffuse for a scent that spreads.
Find more examples of easily confused terms in the guide to confusing words.
