Through Boing Boing:
...I found this interesting story:
...about a developer who declared a "public" street in Silver Spring, MD, to be "private", and banned photography, and the photographers who protested by showing up with their cameras.
The article has this sentence, containing an error that I see fairly often:
To help diffuse the situation, a few days before the July 4th march, the Peterson Company said that it would allow people to take photos in Downtown Silver Spring, but that it could remove this privilege at its discretion.
"Diffuse" means to spread out, as a drop of food colouring diffusing into a glass of water. "Defuse" is the word they want here, which means to reduce/eliminate a source of conflict, using the metaphor of removing the fuse from an explosive device. (The writer repeated his error in the blurb he wrote to Boing Boing, so I don't think it was a typo.)