opsiometer (plural opsiometers)
- An old instrument for measuring vision and determining the focal length of a lens that can correct an individual's imperfect eyesight.
- (Can we find and add a quotation of Brande & C to this entry?)
Part or all of this entry has been imported from the 1913 edition of Webster’s Dictionary, which is now free of copyright and hence in the public domain. The imported definitions may be significantly out of date, and any more recent senses may be completely missing.