Serving, resulting from, or relating to the sense of sight
The mistake, shown in all the old maps of Australia, had originated in a curious optical illusion.
His researches extended to almost every branch of physical science, but his most important work was of an optical character.
in length by any mirrors which can be practically constructed would be like attempting optical experiments with mirrors one-hundred-thousandth of an inch in diameter.
R, Optical section of leptoid (sieve-tube segment) of Phanerogam, with two proteid (companion) cells.
In their optical characters the micas exhibit considerable variations.