*dynameter*

n. [ Gr. &unr_; power + -meter: cf. F. dynamètre. Cf. Dynamometer. ] 1. A dynamometer. [ 1913 Webster ]

2. (Opt.) An instrument for determining the magnifying power of telescopes, consisting usually of a doubleimage micrometer applied to the eye end of a telescope for measuring accurately the diameter of the image of the object glass there formed; which measurement, compared with the actual diameter of the glass, gives the magnifying power. [ 1913 Webster ]