| 释义 |
di·op·ter
\dīˈäptər, ˈdīˌä-\ noun
(-s)
Etymology: Middle French & Latin; Middle French dioptre, from Latin dioptra, from Greek, from dia- + -optra (akin to opsesthai to be going to see)
1. obsolete : an optical instrument invented by Hipparchus for taking altitudes and leveling
2. archaic : a stand or disk revolving about a vertical axis and carrying a lens or prism, leveling sights, or the index arm of a circle according to the kind of instrument to which it was applied : alidade
3. also di·op·tre \“\ : a unit of measurement of the refractive power of a lens equal to the reciprocal of the focal length in meters
4. : an instrument used in craniometry for making projections of the skull |