Kelly day
n.— «The delegation…explained that firemen work one day and have the next day off with every 10th day designated as a “Kelly” day or day off. This schedule is followed except during the vacation period when the Kelly days are granted every 12th day.» —“Board Planning Fire Station Warning Lights” Winona Daily News (Minnesota) May 23, 1957. (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...
The Very Hungry Caterpillar (Bookshop|Amazon) had an earlier title: A Week with Willie the Worm. This is part of a complete episode. Transcript of “The Very Hungry Caterpillar’s First Title” Here’s another book title that...