There are 10 words that start with 'lacto'.
| lactone | lactose |
| lactones | lactonic |
| lactoses | lactogenic |
| lactobacilli | lactobacillus |
| lactoglobulin | lactoglobulins |
Note: These 10 words that start with 'lacto' are found from the USA & Canada version of the tournament Scrabble word list.