Use suffuse to describe things that spread until they fill a space, like the infectious laughter that becomes a roar on a particularly good night at the comedy club. You might say comedy suffuses the area.
Suffuse is a synonym for steep. Like tea whose flavor grows stronger the more it steeps, when you suffuse something it spreads throughout until an area is full, or even overly full. Another synonym, infuse, looks a lot like suffuse. Both words come from the Latin word fundere, which means "to pour."
