There are 14 words that start with 'calm'.
| calm | calms | calmed | 
| calmer | calmly | calmest | 
| calming | calmness | calmative | 
| calmingly | calmatives | calmnesses | 
| calmodulin | calmodulins | |
Note: These 14 words that start with 'calm' are found from the USA & Canada version of the tournament Scrabble word list.