A perch is a temporary resting place. In the middle of climbing a tree, you might find a good perch on a high branch. Bet some birds will be perching there too.
Perch has many different meanings. A bird perch is a little stick it can balance on, and the armrest of the couch can offer you a perch during a party. It's also the name of a kind of fish with spiny fins. And it's also an old measurement of 16.5 feet.