noun
(US McLeod gage)
A type of mercury-in-glass manometer for the absolute measurement of low pressures, in which a known volume of the gas to be measured is compressed by the mercury into a small volume, and the resulting pressure is found from the height of the column of mercury it supports.
Origin
Late 19th century; earliest use found in James Edward Henry Gordon (1852–1893), electrical engineer. From the name of Herbert McLeod, English scientist, who invented the instrument in 1874 (Philos. Mag 48 110) + gauge.
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