Byddarwch, n. deafness
Byddin, n. a snare, an ambush, a band, or troop, an army
Byddiniad, n. an embattling
Byddino, v. to embattle
Byddinol, a. embattling
Byddu, v. to be, to endure
Bygegyr, n. a drone bee
Bygwth, v. to threaten
Bygylu, v. to intimidate
Bygythiad, n. a threatening