The Correct spelling is: penicillin
Common misspellings of the word penicillin are:
How do you spell penicillin?. It is not
Any of a group of broad-spectrum antibiotic drugs obtained from penicillium molds or produced synthetically, most active against gram-positive bacteria and used in the treatment of various infections and diseases.
[PENICILL(IUM) + â€“IN.]