There are 17 words that start with 'slave'.
| slave | slaved | 
| slaver | slaves | 
| slavey | slavers | 
| slavery | slaveys | 
| slavered | slaverer | 
| slaverers | slaveries | 
| slavering | slaveholder | 
| slaveholders | slaveholding | 
| slaveholdings | |
Note: These 17 words that start with 'slave' are found from the USA & Canada version of the tournament Scrabble word list.