Meaning : To certain extent or degree.
							Example : 
							Pretty big.
							Pretty bad.
							Jolly decent of him.
							The shoes are priced reasonably.
							He is fairly clever with computers.
							
Synonyms : fairly, jolly, middling, moderately, passably, reasonably, somewhat
To a degree that exceeds the bounds or reason or moderation.
His prices are unreasonably high.Meaning : Pleasing by delicacy or grace. Not imposing.
							Example : 
							Pretty girl.
							Pretty song.
							Pretty room.
							
Meaning : (used ironically) unexpectedly bad.
							Example : 
							A pretty mess.
							A pretty kettle of fish.