Daunt means to frighten or scare off. The Cowardly Lion's efforts to daunt Dorothy, the Scarecrow, and the Tin Man were less than successful.
Daunt rhymes with haunt, another word which means to frighten, though in a creepier sense. Walking through your neighbors' haunted house on Halloween might daunt your little brother, even though he's unlikely to encounter anything scarier than plastic skeletons and ghosts made of sheets. Daunt often shows up as part of the adjective undaunted, which describes someone who remains unafraid or perseveres in the face of scary circumstances.