Cases of word usage

1) (of a person) sad; depressed; (of eyes) looking downwards (especially with sadness, shame etc) (downcast)

2) to bend, hang, downwards (because of tiredness or weakness) (droop)

3) a quick movement downwards (of the head), especially to show agreement, approval etc (nod)

4) ended; finished; down from a standing position; so that the other of a different side is shown; downwards (over)