Barbaric - civilized, humane, refined
Barrage - trickle, pause
Barren - fertile, productive, fruitful
Barrier - aid, access, opening
Bashful - bold, confident, outgoing
Beacon - deterrent, obscurity, darkness
Bearish - bullish, optimistic
Beckon - dismiss, repel
Befall - avoid, escape
Befitting - unsuitable, inappropriate