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

1.
笑點, 妙語
the final phrase or sentence of a joke or story, providing the humor or climax
:
•
Everyone laughed at the unexpected punch line.
大家都被意想不到的笑點逗笑了。
•
He delivered the punch line with perfect timing.
他以完美的時機說出了笑點。