Word Study
spherometer
CIDE DICTIONARY
spherometer, n. [Sphere + -meter: cf. F. sphéromètre.].
An instrument for measuring the curvature of spherical surface, as of lenses for telescope, etc. [1913 Webster]
OXFORD DICTIONARY
spherometer, n. an instrument for finding the radius of a sphere and for the exact measurement of the thickness of small bodies.
Etymology
F sph{eacute}rom{egrave}tre (as SPHERE, -METER)
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