- (international standards) Indeterminately reserved ISO 3166-1 alpha-2 country code for Bolivia.
- Synonym: BO (for general use)
- (international standards) Indeterminately reserved ISO 3166-1 alpha-2 country code for Botswana.
- Synonym: BW (for general use)
This is an indeterminately reserved code, included as part of ISO 3166-1 on the request of the Secretary-General of the United Nations due to its former use in designating road vehicles under the 1949 Geneva Convention on Road Traffic (in the case of Botswana) and former unofficial usage for a similar purpose (in the case of Bolivia), and is not endorsed for general use by the ISO. The general-purpose codes for Bolivia and Botswana are BO and BW respectively.
RB (plural RBs)
- (American football) Initialism of .