Word Study
altimeter
CIDE DICTIONARY
altimeter, n. [LL. altimeter; altus high + metrum, Gr. , measure: cf. F. altimètre.].
An instrument for taking altitudes, as a quadrant, sextant, etc. Knight. [1913 Webster]
OXFORD DICTIONARY
altimeter, n. an instrument for showing height above sea or ground level, esp. one fitted to an aircraft.
Etymology
L altus high + -METER
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