Septenate or Septennate: How To spell?

The word Septenate is misspelled against Septennate, a noun meaning "A period of seven years; as, the septennate during which the President of the French Republic holds office."

Septennate has double "nn" is mispronounced as "n"
Remember double 'NN' in between the strings septe & ate which should not be misspelled with single 'N'
Wrong Spelling:  septe-n-ate 
Correct Spelling:  septe-nn-ate 
Explore spell check of Septennate to spell without errors.

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