head-knocker
n.— «The man who arranged Moore’s murder was most probably Joseph Neville Cox, the secretary of the Orlando chapter of the Ku Klux Klan, who organized a handful of Klan “head-knockers,” as they were called, arranged to purchase dynamite (which in those days was sold in many hardware stores in Florida) and have it placed beneath Moore’s bedroom.» —“Another Klan bites the dust” by Sam Johns in Jackson, Mississippi BlackNewsWeekly (Chatanooga, Tennessee) Aug. 27, 2007. (source: Double-Tongued Dictionary)
Further reading
Susie Dent’s murder mystery Guilty by Definition (Bookshop|Amazon) follows a lexicographer in Oxford who becomes a sleuth of a different kind, seeking the culprit in a long-unsolved killing. A lexicographer herself, Dent includes lots of obscure and...
In 1968, students at Cheyenne High School in Cheyenne, Wyoming, compiled a collection of their own slang, including the word Clyde, used to refer to one’s head, as in Use your Clyde! This is part of a complete episode.
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