Center letter: b
Outer letter: d e f i l o
Answers (63):
  lifeblood
  bedded
  beef
  beefed
  befell
  belie
  belied
  belief
  bell
  belle
  belled
  bellied
  bible
  bide
  bided
  biff
  biffed
  bifold
  bile
  bill
  billed
  billfold
  bled
  bleed
  blob
  blobbed
  blood
  blooded
  bloodied
  bobbed
  bobble
  bobbled
  bode
  boded
  bodied
  boffo
  boil
  boiled
  bold
  bolded
  boll
  bolo
  boob
  booboo
  boodle
  booed
  doobie
  ebbed
  edible
  feeble
  fibbed
  fobbed
  foible
  libel
  libeled
  libelee
  libido
  lobbed
  lobbied
  lobe
  lobed
  lobo
  oboe