What is the difference between drainage divide and drainage basin?

a drainage basin is where water from rain fall or snow melting drains downhill into a river or stream, or another kind of body of water.http:/en.wikipedia.org/wiki/Drainage_basin a ocean basin is technically anywhere on earth that is covered by seawater. but according to the geologist an ocean basin is below sea level.http:/en.wikipedia.org/wiki/Ocean_basin