PLETH'RON PLETH'RUM, noun [Gr.] A square measure used in Greece, but the contents are not certainly known. Some authors suppose it to correspond with the Roman juger, or 240 feet; others allege it to be double the Egyptian aurora, which was the square of a hundred cubits.
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI