There are 18 words that start with 'overbo'.
| overboil | overbold |
| overbook | overbore |
| overborn | overboard |
| overboils | overbooks |
| overborne | overboiled |
| overbooked | overborrow |
| overbought | overboiling |
| overbooking | overborrows |
| overborrowed | overborrowing |
Note: These 18 words that start with 'overbo' are found from the USA & Canada version of the tournament Scrabble word list.