There are 15 words that start with 'ridge'.
| ridge | ridged | ridgel | 
| ridges | ridgels | ridgetop | 
| ridgeback | ridgeline | ridgeling | 
| ridgepole | ridgetops | ridgebacks | 
| ridgelines | ridgelings | ridgepoles | 
Note: These 15 words that start with 'ridge' are found from the USA & Canada version of the tournament Scrabble word list.