As a proper noun night
is (paganism) the goddess of the night in heathenry.
As a verb must is
to do with certainty; (indicates that the speaker is certain that the subject will have executed the predicate
) or must
can be to make musty.
As a noun must is
something that is mandatory or required or must
can be the property of being stale or musty or must
can be a time during which male elephants exhibit increased levels of sexual activity and aggressiveness (also musth)