punchline (sometimes "punch line")
noun

- the last part of a story or a joke which explains the meaning of what has happened previously or makes it funny

(Cambridge Advanced Learner's Dictionary)

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The word punch has several meanings, including:

- (noun) a piece of equipment which cuts holes in a material by pushing a piece of metal through it

- (noun/verb) a forceful hit with the fist/to hit something with the fist (like a boxing punch)

- (noun) a cold or hot drink made by mixing fruit juices, pieces of fruit and often wine or other alcoholic drinks

- (noun) the power to be interesting and have a strong effect on people

This last definition is the source of the expression "punchline." A punchline is a line (a sentence in this context) that makes a joke work or be funny. For instance:

A bartender notices that a pirate has a wooden leg, a hook for a hand and an eye patch. He asks, "So what happened to the leg?"

"I was swept overboard into a school of sharks during a storm and one of them bit my leg off."

"Wow!" said the bartender "What about your hook"?

"Well, I got hit by a cannonball, it took my arm right off."

"Incredible!" remarked the bartender. "How did you get the eye patch?"

"A seagull flew over the deck and pooped right into my eye."

"And that ruined your eye?"

(now comes the punchline)

"Well," said the pirate, "it was my first day with the hook."

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Practice OWAD in a conversation today, say something like:

"A joke with a good PUNCHLINE can add a little fun to a presentation."