Center letter: n
Outer letter: c g i r u v
Answers (35):
  curving
  cringing
  cuing
  cunning
  curing
  gigging
  ginning
  giving
  grin
  grinning
  gunning
  icing
  incur
  incurring
  inning
  inuring
  inurn
  inurning
  nigiri
  ricin
  ricing
  rigging
  ring
  ringing
  ruin
  ruing
  ruining
  rung
  runic
  running
  ungiving
  unrig
  unrigging
  urging
  virgin