There are 11 13-letter words that start with 'rat'.
| ratifications | ratiocinating |
| ratiocination | ratiocinative |
| ratiocinators | rationalising |
| rationalistic | rationalities |
| rationalizers | rationalizing |
| rattlebrained | |
Note: These 11 13-letter words that start with 'rat' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with rati, ratt, rata, rate, rato, rath, ratc, ratl, ratf, rats, ratb.
4-letter words start with 'rat' (4)