Oolong tea is sometimes called 'wulong' (also pronounced 'oolong') or 'black dragon' tea.
Oolong teas are semi-oxidized teas. They are sometimes called 'semi-fermented teas,' though this moniker is considered to be less technically correct than semi-oxidized teas. After the tealeaves are picked, they are rolled and allowed to oxidize. Oxidation produces the floral notes that characterize many oolongs.