The word "tannosal" is an uncommon term that refers to an organic compound used in the leather industry. Its spelling may seem confusing at first glance, but the IPA phonetic transcription can clarify it. The word is pronounced /ˌtænəˈsoʊl/, with the stress on the middle syllable. Its spelling reflects the relationship between the phonemes in "tannin" and "phenol", which are combined to form the word. While this term may not be familiar to many, its spelling can be easily understood with the help of phonetics.
Creosal, creosoti tannas.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.