means A spoiler is either an aerodynamic part fitted to a vehicle to disrupt unwanted airflow and improve stability, or a piece of information that reveals a plot twist before someone wants to know it.

from From the verb 'spoil,' which came through Old French 'espoillier' from Latin 'spoliare,' meaning to strip or plunder — originally to strip an enemy of armor and goods. 'Spoil' first meant ruin or pillage; the noun 'spoiler' followed as 'one who spoils.' The car part is a 20th-century borrowing — the wing 'spoils' the smooth airflow on purpose — while the plot-twist sense is even more recent, spoiling the surprise rather than a battlefield.