When people are at loggerheads, they are in conflict and unable to agree. The origin of the phrase is apparently unclear. In 16th-century England, a loggerhead was a heavy block of wood to which horses were tethered to keep them from wandering away. In those days, loggerhead also meant a stupid person, a blockhead. In the next century, a certain kind of heavy iron tool was also called a loggerhead. The assumption is that people who were in conflict were said to be at loggerheads because the conflict makes one think of fighting with such dangerous items. The original meaning of loggerhead survives in the name of the loggerhead turtle, which is named that because of its unusually large head.
(Will be published in the April 2010 issue of Denver's Community News.)
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