Bipenated or Bipennated: How To spell?
The word Bipenated is misspelled against Bipennated, an adjective meaning "Having two wings."
Bipennated has double "nn" is mispronounced as "n"Remember double 'NN' in between the strings bipe & ated which should not be misspelled with single 'N'
Wrong Spelling:  bipe-n-ated  Correct Spelling:  bipe-nn-ated 
Find more wrongly spelled words of Bipennated to spell it well.