There are conflicting definitions of origin. Unclear as to whether it is derived directly from the Greek, coined by Pearson, or used and named prior to Pearson.
Refer to "The History of Histograms - 1. Prehistory" - Yannis Ioannidis
The etymology of the word histogram is uncertain. Sometimes it is said to be derived from the Greek histos 'anything set upright' (as the masts of a ship, the bar of a loom, or the vertical bars of a histogram); and gramma 'drawing, record, writing'. It is also said that Karl Pearson, who introduced the term in 1895, derived the name from "historical diagram".
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