There are 21 words that start with 'suck'.
suck | sucks | sucky |
sucked | sucker | suckle |
suckers | suckier | sucking |
suckled | suckler | suckles |
suckered | suckfish | suckiest |
sucklers | suckless | suckling |
suckering | sucklings | suckfishes |
Note: These 21 words that start with 'suck' are found from the USA & Canada version of the tournament Scrabble word list.