Center letter: e
Outer letter: f i l n o x
Answers (35):
  flexion
  elfin
  exile
  feel
  feline
  fell
  felon
  fennel
  fief
  fife
  file
  fine
  flee
  flex
  floe
  innie
  leonine
  lien
  life
  lifeline
  line
  linen
  lone
  loonie
  nene
  neon
  nine
  noel
  none
  offline
  oleo
  ollie
  online
  oxen
  xenon