Lying in bed with my thoughts I have stumbled across a problem. It looks like this:

revel – lever
team – meat
nib – bin
tip – pit
real – lear
made – edam
desserts – stressed

What are they?

Now, I know that they are palindromes when placed together, what I want to know is the name of a word that changes its meaning when reversed. If you know the answer then for the sake of my sanity please post it in a comment. Also, I’d be interested to see any others that you can come up with.