top·per 
(tŏpər)
(tŏpər)n.
1. One that removes tops or puts tops on.
2. Something that goes on top of something else: a mattress topper; cake topper.
3. See truck cap.
4.
a. A short, lightweight coat.
b. Informal A top hat.
5.
a. One that is exceedingly or surpassingly good of its kind.
b. Informal Something, such as a witticism, that surpasses all that has gone before.