athlete’s clock
n.— «The Huskies had hoped Miller would still be granted four years of eligibility and that the five-year window each athlete is given—commonly called an athlete’s clock—would not have started in that summer of 2006.» —“Miller settles in at tackle for UConn” by Neill Ostrout in Storrs Connecticut Post (Bridgeport) Mar. 31, 2008. (source: Double-Tongued Dictionary)
Further reading
What’s up with ketchup? The shifting history and spelling of the name of this condiment. For centuries, ketchup was a fishy sauce originating in Asia—the tomatoes came only later! Plus, a new book shows what’s lost when a language dies: when there...
In a 1968 list of Cheyenne High School slang that ran in newspapers around the United States, Clyde, written like the man’s name, meant one’s head or mind. The Wyoming students’ examples included Use your Clyde! and put it out of your Clyde...