Bitern or Bittern: How To spell?
The word Bitern is misspelled against Bittern, a noun meaning "A wading bird of the genus Botaurus, allied to the herons, of various species."
Bittern has double "tt" is mispronounced as "t"Remember double 'TT' in between the strings bi & ern which should not be misspelled with single 'T'
Wrong Spelling:  bi-t-ern  Correct Spelling:  bi-tt-ern 
Find more wrongly spelled words of Bittern to spell it well.