There are 25 6-letter words that start with 'boo'.
| boobed | boobie | booboo | boocoo | boodle | 
| booger | boogey | boogie | boohoo | booing | 
| boojum | booked | booker | bookie | bookoo | 
| boomed | boomer | boosts | booted | bootee | 
| booths | bootie | boozed | boozer | boozes | 
Note: These 25 6-letter words that start with 'boo' are found from the USA & Canada version of the tournament Scrabble word list.
Also see words start with book, boot, boom, boog, boob, boon, booz, boos, bood, boor, booh, booc, booj, booe, booi.
4-letter words start with 'boo' (7)