There are 9 words that start with 'ratioc'.
| ratiocinate | ratiocinated |
| ratiocinates | ratiocinator |
| ratiocinating | ratiocination |
| ratiocinative | ratiocinators |
| ratiocinations | |
Note: These 9 words that start with 'ratioc' are found from the USA & Canada version of the tournament Scrabble word list.