Center letter: p
Outer letter: f g i l n o
Answers (54):
  flipflopping
  flopping
  fillip
  flip
  flipflop
  flipping
  flop
  gloop
  glop
  glopping
  goop
  lipo
  lipping
  lollipop
  lollop
  lolloping
  loop
  looping
  loping
  lopping
  nipping
  opining
  opinion
  piffling
  pigging
  piling
  pill
  pilling
  pillion
  ping
  pinging
  pining
  pinion
  pinioning
  pinning
  piping
  pippin
  plop
  plopping
  pogo
  pogoing
  poling
  polio
  poll
  polling
  polo
  pong
  poof
  pool
  pooling
  poop
  pooping
  poplin
  popping