Bamako
geographical name
Ba·ma·ko ˈbä-mä-ˌkō 
city and capital of Mali on the Niger River population 1,016,167
- on balance
- on base
- on behalf of
- on behalf of someone
- on bended knee
- on benefits
- on bluegrass
- on board
- on both counts
- on both sides
- on brand
- on call
- on camera
- on campus
- on closer inspection
- on cloud nine
- on command
- on commission
- on company time
- on condition of anonymity
- on condition that
- on consignment
- on contact
- on creek
- on crutches