There are 15 words that start with 'besti'.
| bestir | bestial | besting |
| bestirs | bestiary | bestially |
| bestirred | bestiality | bestialize |
| bestiaries | bestirring | bestialized |
| bestializes | bestialities | bestializing |
Note: These 15 words that start with 'besti' are found from the USA & Canada version of the tournament Scrabble word list.