Center letter: o
Outer letter: t b h i l n
Answers (53):
  billionth
  billion
  biotin
  blob
  blot
  blotto
  bobbin
  boho
  boil
  boll
  bolo
  bolt
  bonbon
  bonito
  bonobo
  boob
  booboo
  boohoo
  boon
  boot
  booth
  both
  hobbit
  hobnob
  hobo
  holt
  hoot
  inhibition
  into
  lion
  litho
  lobo
  loin
  loll
  loon
  loot
  lotion
  lotto
  nonillion
  noob
  noon
  notion
  obit
  olio
  onion
  onto
  toil
  toll
  tollbooth
  tool
  toon
  toot
  tooth