There are 15 12-letter words that start with 'mot'.
| motherboards | motherfucker | motherhouses | 
| motherliness | mothproofers | mothproofing | 
| motionlessly | motivational | motivelessly | 
| motoneuronal | motorboaters | motorboating | 
| motorcycling | motorcyclist | motorization | 
Note: These 15 12-letter words that start with 'mot' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with moto, moth, moti, mott, mote, motl, motm, mots.
4-letter words start with 'mot' (4)