Gresorious or Gressorious: How To spell?
The word Gresorious is misspelled against Gressorious, an adjective meaning "Adapted for walking; anisodactylous; as the feet of certain birds and insects. See Illust. under Aves."
Gressorious has double "ss" is mispronounced as "s"Remember double 'SS' in between the strings gre & orious which should not be misspelled with single 'S'
Wrong Spelling:  gre-s-orious  Correct Spelling:  gre-ss-orious 
Check more misspelled words of Gressorious to spell it correct.