Herunter
Herunter is a German directional particle that conveys downward movement, often toward the speaker or a lower position. It combines with other elements to form verbs and phrases, functioning both as an adverb and as part of separable verb prefixes. The component is historically related to the particles her (toward this place) and unter (under/down).
In modern usage, herunter appears in two main ways. As a separate adverb, it describes downward movement:
Common verbs with the prefix herunter include herunterfallen (to fall down), herunterbringen (to bring down/to deliver
See also: prefixes in German, separable-prefix verbs, headed-down movement in German syntax.