Microrganism or Microorganism: How To spell?
The word Microrganism is misspelled against Microorganism, a noun meaning "Any microscopic form of life; -- particularly applied to bacteria and similar organisms, esp. such are supposed to cause infectious diseases."
Microorganism has double "oo" is mispronounced as "o"Remember double 'OO' in between the strings micr & rganism which should not be misspelled with single 'O'
Wrong Spelling:  micr-o-rganism  Correct Spelling:  micr-oo-rganism 
Find more incorrect spellings of Microorganism to spell right way.