sight
The origin for 'optical' is Latin
One example of a sentence with the word "optical" in it would be: He looked at the optical illusion on the piece of paper.
The mirage was just an optical illusion.
Optical refers to the eyes or vision. The optical lenses must be ground carefully.
If you mean a noun that is defined as anything that gets in the way of; a hindrance; an obstruction The word is OBSTACLE. If you mean the word used to describe the behaviour and properties of light and how it interacts with matter then the word is spelt OPTICS / OPTICAL.
"optique"
Optic or optical
I believe this is due to an optical mix-up. Either it is ΕΠΙΡΡΗΜΑ standing for : Adverb or it is ΑΙΝΙΓΜΑ standing for: Riddle
"radlb" does not mean anything in French. It is a frequent typo for the word "radio" made by optical character recognition systems, for instance on Google scanned books.
optical?
"Foctus" is not a word in English. -You may mean 'focus' -the distinctness or clarity of an image rendered by an optical system, or a center of interest or activity
"Optical" is considered to have a long vowel sound. The letter "o" is pronounced as the long "o" sound /oʊ/ in this word.