The correct spelling of the word "Tetanin" is actually "Tetanolin". The reason for this spelling discrepancy is due to a historical error made during the production of commercial tetanus vaccines. The misnomer became widely used and is still prevalent today. The word is pronounced as /tɛˈtænəlɪn/ in IPA phonetic transcription, with the primary stress on the second syllable. Tetanolin is an important vaccine used to prevent tetanus, which is a serious bacterial infection.
Tetanotoxin.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.