| Brobdingnagian | adj. | stupendously huge | ||
| bromide | n. | chemical compound based upon bromine; medicament from such a compound, esp. lithium bromide, formerly used as antidepressant at beginning of 20th C.; platitude; dullard | ||
| brontide | n. | sound of distant thunder | ||
| brothel creeper | n. | shoe with thick crepe sole, often with suede uppers | ||
| brumation | n. | period of torpor and sluggish activity | ||
| Brummagem | adj. | gaudy and cheap; fake, counterfeit | ||
| brunser | n. | male homosexual, esp. younger partner of a pair | slang | |
| brychan | n. | rough wool blanket | ||
| bubblehead | n. | dolt, stupid person | ||
| bubo | n. | inflamed swelling of lymphatic gland, esp. in groin or armpit | ||
| buccal | adj. | of or related to the cheek | ||
| buckshee | adj. | extra, free | slang | |
| bucranium | n. | sculpted ox skull used as decoration | architecture | |
| budge | n. | lambskin fur | ||
| bugfuck | adj. | crazy, whackadoodle | ||
| Buggins’s turn | n. | possession of office by rotation or seniority rather than merit | idiom | |
| buhl | n. | brass, pewter, tortoiseshell, etc. inlaid as decoration | ||
| bulla | n. | blister, vesicle; hollow spaces within bone structures; clay balls or containers, often with external writing detailing contents; papal letters | biology | |
| bumbailiff | n. | low-rank bailiff | ||
| bumbaste | v. | to beat on the buttocks; thus, to beat soundly | ||
| bumboat | n. | small boat selling provisions or wares to ships in port or offshore | ||
| bumph | n. | useless papers or documents | British | |
| buncombe | n. | humbug, claptrap; mere speechifying | ||
| bund | n. | causeway, embankment; secondary retaining wall surrounding tank for fluid | ||
| bunny boiler | n. | vengeful former partner after being spurned, usu. of a woman | slang | |
| bunt | n. | reinforced part of fishing net where the catch is concentrated; bulging middle part of a sail | nautical | |
| bunting | n. | open worsted fabric used for making flags; thus, a flag or flags | ||
| burble | n. | (aeronautics) breakdown of smooth airflow into turbulence | ||
| burgage | n. | tenure of land in town belonging to the king or other lord, the tenants paying annual rent or service | ||
| burgee | n. | triangular flag or one having a triangular indentation leaving two tails | ||
| burgeon | v. | to begin to grow | ||
| burgonet | n. | light helmet for infantrymen with protective crest and cheek pieces | ||
| burin | n. | engraving tool for use on metal | ||
| burke | v. | to kill by suffocation or strangulation so as to leave no trace; to hush up | ||
| burlesque | n. | art form that inverts the usual mode of presenting material for comedic effect, giving gravitas to lesser subjects or treating vulgarly more dignified matter | ||
| burr | v. | to speak with strongly rolled r’s, to make whirring sounds; to fashion a rough edge upon metal | ||
| burrnesha | n. | Balkan sworn virgins, women in parts of western Balkan regions who take an oath of celibacy and gain privileges otherwise available only to men | ||
| bursary | n. | college scholarship; institutional treasure, esp. for ecclesiastical institutions | British | |
| busby | n. | tall fur hat with colored cloth hanging down right side; tall bearskin hat | ||
| buskin | n. | half boot; thick-soled shoe worn by ancient Greek actors in tragedies, cothurnus; [fig.] tragedy, the style of tragedy | ||
| but and ben | n. | simple two-room cottage | architecture | |
| butt splice | n. | cylindrical crimp connector for electrical wiring, with a crimp at each end | ||
| buttle | v. | to act as a butler | ||
| butty | n. | 1 | buttered bread; sandwich | idiom |
| butty | n. | 2 | co-worker or work friend, esp. in colliery | |
| buy a brush | v. | to run away | slang | |
| byre | n. | shed for cows | ||
| cachalot | n. | sperm whale | ||
| cachectic | adj. | of or pertaining to general malaise with malnutrition; related to a depraved habit or mind or feeling | ||
| cachinnation | n. | immoderate or loud laughter |
