There are 12 words that end with 'osin'.
eosin | rosin | myosin |
pocosin | tylosin | chymosin |
nigrosin | thymosin | actomyosin |
meromyosin | erythrosin | tropomyosin |
Note: These 12 words that end with 'osin' are found from the USA & Canada version of the tournament Scrabble word list.