Center letter: n
Outer letter: d i k l u y
Answers (21):
  unkindly
  dink
  dinky
  dunk
  inky
  kiln
  kind
  kindly
  kink
  kinkily
  kinky
  link
  lunk
  ninny
  nudnik
  null
  undid
  unduly
  unkind
  unkink
  unlink