How do you spell Optical

Available Definitions:
1)  a. - Of or pertaining to vision or sight.
2)  a. - Of or pertaining to the eye; ocular; as, the optic nerves (the first pair of cranial nerves) which are distributed to the retina. See Illust . of Brain, and Eye.
3)  a. - Relating to the science of optics; as, optical works.