punch line
US /ˈpʌntʃ ˌlaɪn/
UK /ˈpʌntʃ ˌlaɪn/

1.
remate, chiste final
the final phrase or sentence of a joke or story, providing the humor or climax
:
•
Everyone laughed at the unexpected punch line.
Todos se rieron del inesperado remate.
•
He delivered the punch line with perfect timing.
Entregó el remate con una sincronización perfecta.