Evening (eve) before the following day; eve of a celebration (and its festivities).
The day is counted from nightfall of one day to sundown of the next, so the malam is the first part of any 24 hour period bahangi.
Malam tabu'.
The evening of (i.e. before) market day.
Nina' malam pangawin siyehin.
Tonight is the eve of their wedding.