| Acronym | Definition |
|---|
| BU | Backup |
| BU | Bulletin |
| BU | Boston University |
| BU | Bureau |
| BU | Bulgaria |
| BU | Builder (USN Rating) |
| BU | Baylor University |
| BU | Break Up |
| BU | Build Up (semiconductor substrate process) |
| BU | Business Unit |
| BU | Bushel |
| BU | Bibliothèque Universitaire (French) |
| BU | Brown University |
| BU | Binghamton University (SUNY Binghamton) |
| BU | Belly Up |
| BU | Braathens (Airline) |
| BU | Binding Update |
| BU | Bethel University |
| BU | Bottom Up (model) |
| BU | Baptist University (Hong Kong) |
| BU | Brandeis University |
| BU | Bloomsburg University (Pennsylvania) |
| BU | Bradley University |
| BU | Bellevue University |
| BU | Bogazici University |
| BU | Bangkok University (Thailand) |
| BU | Brandon University |
| BU | Belmont University |
| BU | Brilliant Uncirculated (numismatics) |
| BU | Basic Understanding |
| BU | Bargaining Unit (Employee) |
| BU | Bishop's University (Lennoxville, Quebec, Canada) |
| BU | Bucknell University |
| BU | Brock University |
| BU | Bilkent University |
| BU | Butler University |
| BU | Baker University (Baldwin City, KS) |
| BU | Buruli Ulcer |
| BU | Bangalore University (India) |
| BU | Basically Useless |
| BU | Blue Underground (DVD supplier) |
| BU | Bicol University |
| Bu | Butyl Group (chemistry) |
| BU | Bergen University (Bergen, Norway) |
| BU | Bluffton University (Bluffton, OH) |
| BU | Baskent University (Adana, Turkey) |
| BU | Bethesda Unit |
| BU | Brooklyn Union (Brooklyn Rapid Transit system) |
| BU | Bahçesehir Üniversitesi (Istanbul, Turkey) |
| BU | Billion Unit |
| BU | Billing Unit |
| BU | Ballast Unit |
| BU | Bad Urban Area (terrain type) |
| BU | Base of Prism Up |
| BU | Bande d'Usure (French, accordion bellows protection) |
| BU | Brass Unlimited (Tacoma, WA) |