There are 11 15-letter words that start with 'inf'.
| infallibilities | infantilization | 
| infeasibilities | infinitesimally | 
| inflammableness | inflexibilities | 
| informationally | informativeness | 
| infrastructures | infundibuliform | 
| infusiblenesses | |
Note: These 11 15-letter words that start with 'inf' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with infl, infe, infi, infa, info, infr, infu.
4-letter words start with 'inf' (1)