Word #1

Word: Mirthful

Original sentence: "Sustained mirthful laughter--the kind stimulated by, say, the Marx Brothers--has been shown to provide benefits that include improving blood flow, lowering levels of the stress hormone cortisol and boosting the immune system." (source: Time magazine, September 13, 2010.)

Merriam-Webster dictionary definition: (for "mirth") "Gladness or gaiety as shown by or accompanied with laughter."
"Mirthful" is an adjective.

My sentence: "When Josh told me his latest one-liner, I burst into such an extreme bout of mirthful laughter that I almost fell of my chair."