There are 16 words that start with 'sixt'.
| sixte | sixth | sixty | 
| sixtes | sixths | sixteen | 
| sixthly | sixties | sixteens | 
| sixtieth | sixtyish | sixteenmo | 
| sixteenth | sixtieths | sixteenmos | 
| sixteenths | ||
Note: These 16 words that start with 'sixt' are found from the USA & Canada version of the tournament Scrabble word list.