bathing-costume (also bathing-suit)

n (Brit becoming dated 渐旧) = swimming-costume (swim).

bastardy, baste, Bastille, bastinado, bastion, bat, batch, batch processing, bated, bath, bath chair, bath mat, bath-tub, bathe, bathed, bather, bathetic, bathing, bathing suit, bathing-cap, bathos, bathrobe (also robe), bathroom, bathysphere, batik, batiste, batman, baton, bats, batsman, battalion, batten, batter, battered, batteries, battering ram, battering-ram, battery, battery farm, battle,