Center letter: d
Outer letter: a b c i r t
Answers (32):
  catbird
  abracadabra
  acid
  acidic
  acrid
  addict
  arcadia
  arid
  bard
  bird
  brad
  braid
  card
  cardiac
  cicada
  dart
  data
  diacritic
  dicta
  didact
  didactic
  dirt
  drab
  drat
  drib
  rabid
  radar
  radii
  raid
  tabard
  tidbit
  triad