- doA syntactic marker in a question whose main verb is not another auxiliary verb or be.
- lordThe master of the servants of a household; (historical) the master of a feudal manor
- danA title of honour or respect similar to "master" or "Sir", used of historical and legendary figures of the past.
- donA university professor, particularly one at Oxford or Cambridge.
- dungeonAn underground prison or vault, typically built underneath a castle.
- dominusmaster; sir; a title of respect formerly applied to a knight or clergyman, and sometimes to the lord of a manor, castle or an academic master
- domineLord; master.
- donzelA young squire or the attendant to a knight; a page