B
- back and forth
- back at you
- back away
- back down
- back in the day
- back off
- back out
- back then
- back to back
- back to square one
- back to the drawing board
- back up
- backhanded compliment
- bad apple
- bad blood
- bad hair day
- bad news
- bail out
- baker's dozen
- bang for the buck
- barge in
- bark up the wrong tree
- based on
- bat an eye
- bat for the other team
- batten down the hatches
- bawl out
- be about
- be going to
- be like
- be my guest
- be oneself
- be that as it may
- bear fruit
- bear in mind
- bear the brunt
- bear with
- bear witness
- beat a dead horse
- beat around the bush
- beat down
- beat it
- beat to the punch
- beat up
- beats me
- because of
- beef up
- before long
- beg to differ
- behind bars
- behind closed doors
- behind someone's back
- behind the scenes
- behind the wheel
- believe in
- believe it or not
- bells and whistles
- belong to
- below the belt
- bend over backwards
- beside oneself
- beside the point
- best bet
- best laid plans
- best of all
- best of both worlds
- best regards
- best thing since sliced bread
- bet on
- better off
- between you and me
- beyond a doubt
- beyond a reasonable doubt
- beyond a shadow of a doubt
- beyond the pale
- bide one's time
- big boy
- big break
- big deal
- big money
- big mouth
- big picture
- big shot
- bigger fish to fry
- bird's-eye view
- birds and bees
- birds of a feather
- birthday suit
- bit by bit
- bite one's tongue
- bite the bullet
- bite the dust
- bits and bobs
- bitter end
- black and white
- black out
- black sheep
- blast from the past
- blast off
- blend in
- bless you
- blink of an eye
- blow a fuse
- blow a gasket
- blow a kiss
- blow away
- blow off
- blow off steam
- blow out
- blow out of proportion
- blow over
- blow someone's mind
- blow the whistle
- blow up
- blurt out
- bog down
- bogged down
- boil down
- boiling point
- bolt from the blue
- bone of contention
- bone to pick
- boot up
- born and bred
- borrowed time
- bottle up
- bottom line
- bottom out
- bounce back
- bounce off
- bow down
- bow out
- bowl over
- brain drain
- bread and butter
- break a leg
- break a sweat
- break away
- break down
- break even
- break in
- break into
- break it down
- break off
- break out
- break someone's heart
- break the bank
- break the ice
- break the mold
- break through
- break up
- break wind
- breathe down someone's neck
- bridge the gap
- bright side
- brighten up
- bring about
- bring back
- bring down
- bring forward
- bring home
- bring home the bacon
- bring in
- bring it
- bring on
- bring out
- bring to bear
- bring up
- broad strokes
- broadly speaking
- broken record
- brush off
- brush up
- buck the trend
- buck up
- bucket list
- buckle down
- buckle up
- bugger off
- build on
- build up
- bull in a china shop
- bump in the road
- bump into
- bump off
- bump up
- bundle of joy
- burn down
- burn one's bridges
- burn out
- burn the candle at both ends
- burn the midnight oil
- burn up
- burst into tears
- burst out
- burst someone's bubble
- bury one's head in the sand
- bury the hatchet
- business as usual
- bust out
- bust up
- butt heads
- butt in
- butter up
- button up
- buy off
- buy out
- buy time
- by a hair's breadth
- by a landslide
- by a long shot
- by accident
- by all means
- by and large
- by any chance
- by any means
- by chance
- by choice
- by contrast
- by default
- by definition
- by extension
- by far
- by hand
- by heart
- by means of
- by mistake
- by nature
- by no means
- by now
- by oneself
- by the book
- by the same token
- by the skin of one's teeth
- by the way
- by trade
- by virtue of
- by way of