alligator arms
n.pl.— «Some of the best players in the NBA have developed “alligator arms”— sports parlance for not extending the arms—under the pressure of big free throws.» —“The fine art of shooting free throws” by Eric Plummer Bonner County Daily Bee (Sandpoint, Idaho) Dec. 31, 2008. (source: Double-Tongued Dictionary)
Further reading
Susan from Virginia Beach, Virginia, shares the phrase her mother used when the kids refused to eat: It’ll grow hair on your back teeth. This supposed motivator likely blends two older traditions: a German idiom, Haare auf den Zähnen haben...
Why do speakers of the same language have different accents? A lively new book called Why We Talk Funny offers a linguist’s look at how and why accents develop. And: If you’ve “stood up” at a wedding, were you supporting the marriage or objecting to...