1. IB - Noun
2. IB - Proper noun
(education) Initialism of International Baccalaureate.
Coordinate terms: IBO, AP
(finance) Initialism of investment banking.
(education) An International Baccalaureate program
Coordinate term: AP
(military) Initialism of integrated battlefield.
(pathology) Initialism of infectious bronchitis.
Source: en.wiktionary.org