Center letter: k
Outer letter: g i n o t u
Answers (26):
  unknotting
  ginkgo
  gunk
  inking
  king
  kinging
  kink
  kinking
  kiting
  knit
  knitting
  knot
  knotting
  kook
  nook
  nuking
  oink
  oinking
  tiki
  toking
  took
  unkink
  unkinking
  unknit
  unknitting
  unknot