buoy ‧ an ‧ cy /ˈbɔɪənsi $ ˈbɔɪənsi, ˈbuːjənsi/ BrE AmE noun [uncountable]
1 . the ability of an object to float
2 . the power of a liquid to make an object float:
Salt water has more buoyancy than fresh water.
3 . a feeling of happiness and a belief that you can deal with problems easily
4 . the ability of prices, a business etc to quickly get back to a high level after a difficult period