| Defiance to Oswego (Illinois) | 207.42 mi (333.81 km) |
| Defiance to Oswego (New York) | 428.39 mi (689.43 km) |
| Defiance to Otsego (Minnesota) | 540.37 mi (869.64 km) |
| Defiance to Ottawa (Illinois) | 231.49 mi (372.55 km) |
| Defiance to Ottawa (Kansas) | 605.82 mi (974.97 km) |
| Defiance to Ottumwa (Iowa) | 419.20 mi (674.64 km) |
| Defiance to Overland (Missouri) | 364.41 mi (586.46 km) |
| Defiance to Overland Park (Kansas) | 569.73 mi (916.90 km) |
| Defiance to Overlea (Maryland) | 433.94 mi (698.36 km) |
| Defiance to Oviedo (Florida) | 890.37 mi (1,432.92 km) |
| Defiance to Owasso (Oklahoma) | 706.50 mi (1,137.01 km) |
| Defiance to Owatonna (Minnesota) | 490.00 mi (788.59 km) |
| Defiance to Owensboro (Kentucky) | 284.19 mi (457.36 km) |
| Defiance to Owings Mills (Maryland) | 419.09 mi (674.46 km) |
| Defiance to Owosso (Michigan) | 118.84 mi (191.25 km) |
