Synesthesia is defined as: The use of one sense to convey the experience of another.
So for example, a lot people convey feelings through the eyes (the sense of sight) as oppose to saying it verbally (the sense of speech). Or vice versa. This term reminds me of a game we just played at my friends house for her birthday. She was blind-folded and had to use all her other senses to figure out who was in front of her. It was a fun night. :)
You know what comes next...examples...
Funky, right? Imagine doing everything we normally do with another sense: Smelling a CD instead of listening to it? Listening to food instead of tasting it?
Do you hear anger when you see red? Taste bubblegum when you see pink?