| Blue-and-yellow Macaw | Ara ararauna |
| Blue-bellied Roller | Coracias cyanogaster |
| Blue-billed Duck | Oxyura australis |
| blue-black | azul oscuro |
| blue-chip securities | acciones selectas |
| blue-collar worker | obrero |
| Blue-crowned Parakeet | Aratinga acuticaudata |
| blue-eyed | de ojos azules |
| Blue-eyed grass | Sisyrinchium |
| Blue-eyed soul | Blue eyed soul |
| Blue-footed Booby | Sula nebouxii |
| Blue-fronted Amazon | Amazona aestiva |
| blue-green alga | alga verde-azul |
| Blue-headed Wood-dove | Turtur brehmeri |
| blue-pencil | eliminar |
| Blue-throated Macaw | Ara glaucogularis |
| Blue-tongued skink | Tiliqua |
| Blue-winged Goose | Cyanochen cyanopterus |
| Blue-winged Macaw | Primolius maracana |
| Blue-winged Teal | Anas discors |
| Bluebeard | Barba Azul |
| bluebell | campanilla |
| blueberry | arándano |
| bluebird | pájaro azul |
| bluebottle | aciano |
| Bluebuck | Hippotragus leucophaeus |
| Bluegrass music | Bluegrass |
| Bluegrass State | Kentucky |
| bluejeans | pantalones |
| blueprint | cianotipo |
| blues | nostalgia |
| Blues Brothers | The Blues Brothers |
| Blues for the Red Sun | Blues for the Red Sun |
| Blues standard | Blues estándar |
| Blues-rock | Blues rock |
| bluestocking | literata |
| bluethroat | pechiazul |
| bluetongue | lengua azul |
| Bluetongue disease | Virus de la lengua azul |
| Bluetongue outbreak in Germany | Brote de virus de lengua azul causa la muerte de miles de ovejas en Alemania |
| Bluetooth | Bluetooth |
| Bluetooth protocols | Protocolos Bluetooth |
| Bluetooth stack | Bluetooth stack |
| bluffer | fanfarrona |
| bluing | añil |
| bluish | azulado |
| Bluma Zeigarnik | Bluma Zeigarnik |
| Blumberg sign | Signo de Blumberg |
| Blumenstein | Blumenstein |
| blunder | equivocación |
| blunderbuss | trabuco |
| blunderer | torpe |
| blunt | franco |
| bluntly | simplemente |
| bluntness | brusquedad |
| blur | borrón |
| blurb | propaganda encomiástica |
| blurred | nublado |
| blurry | borroso |
| blurt | hablar sin tino |
| blush | ruborizarse |
| blusher | colorete |
| blushing | ruboroso |
| bluster | jactarse |
| blustering | borrascoso |
| blustery | tempestuoso |
| Blutengel | Blutengel |
| Bluto | Bruto |
| blutworst | morcilla |
| Blériot XI | Blériot XI |
| Blót | Blót |
| Blücher | Blücher |
| Blümchen | Jasmin Wagner |
| Blüthner | Bluthner |
| BM Altea | Club Balonmano Altea |
| BM Ciudad de Almería | Balonmano Ciudad de Almería |
| BM Ciudad Real | Club Balonmano Ciudad Real |
| BM Granollers | Club Balonmano Granollers |
| BM Valladolid | Club Balonmano Valladolid |
| BMI | Bmi |
| BMP file format | Windows bitmap |
| BMV | BWV |
| BMW | BMW |
| BMW CS Concept | BMW CS |
| BMW Mini | Mini |
| BMW motorcycles | BMW |
| BMX | BMX |
| BMX racing | BMX |
| BNC connector | BNC |
| BNDES | Banco Nacional de Desenvolvimento Econômico e Social |
| Bnei Akiva | Bnei Akiva |
| Bnei Brak | Bnei Brak |
| BNFL | BNFL |
| BNSF Railway | Burlington Northern Santa Fe |
| Bo | Bō |
| Bo Diddley | Bo Diddley |
| Bo District | Distrito de Bo |
| boa | boa |
| boa constrictor | boa constrictora |
| Boaco | Boaco |
| Boadicea | Boudica |
| boar | jabalí |
| board | embarcarse |
| board a train | subir al tren |
| board and lodging | comida y alojamiento |
| board game | juego de tablero |
| board of directors | consejo de administración |
| Board of European Students of Technology | Consejo de Estudiantes Europeos de Tecnología |
| board up | clavar |
| boarding | entablado |
| boarding card | tarjeta de embarque |
| boarding house | pensión |
| boarding pass | tarjeta de embarque |
| boarding school | internado |
