Renin or Rennin: How To spell?
The word Renin is misspelled against Rennin, a noun meaning "A milk-clotting enzyme obtained from the true stomach (abomasum) of a suckling calf. Mol. wt. about 31,000. Also called chymosin, rennase, and abomasal enzyme."
Rennin has double "nn" is mispronounced as "n"Remember double 'NN' in between the strings re & in which should not be misspelled with single 'N'
Wrong Spelling:  re-n-in  Correct Spelling:  re-nn-in 
Find more wrongly spelled words of Rennin to spell it well.