Center letter: h
Outer letter: a d e i n p
Answers (26):
  headpin
  pinhead
  pinheaded
  ahead
  aphid
  daphne
  deadhead
  deadheaded
  hand
  handed
  happen
  happened
  head
  headed
  heap
  heaped
  heed
  heeded
  heinie
  henna
  hennaed
  hidden
  hide
  hind
  hippie
  peahen