1) Belly laugh 2) Big Broadway hit 3) Big hit on broadway 4) Big laugh 5) Big laugh elicitor 6) Big laugh or success 7) Box office smash 8) Gag line 9) Hit on broadway 10) Hit to show biz insiders 11) Knee-slapping joke 12) Line that elicits a big laugh 13) Loud hearty laugh 14) Slang for to hit or punch 
Boff is slang for to hit or punch.