Full Definition of COLLECTIVE. 1. 2. a: formed by collecting: aggregated b of a fruit: multiple. 3. a: of, relating to, or being a group of individuals. 4. : marked by similarity among or with the members of a group.5. : collectivized or characterized by collectivism.ull Definition of COLLECTIVE. 1. : a collective body: group. 2. : a cooperative unit or organization; specifically: collective farm. 3. : a helicopter control system governing lift. See collective defined for English-language learners.
Listen. The most common vision problems are refractive errors, more commonly known as nearsightedness, farsightedness, astigmatism and presbyopia. Refractive errors occur when the shape of the eye prevents light from focusing directly on the retina.ision occurs when light rays are bent (refracted) as they pass through the cornea and the lens. The light is then focused on the retina. The retina converts the light-rays into messages that are sent through the optic nerve to the brain. The brain interprets these messages into the images we see.
Retinal artery occlusion occurs when the retinal artery (or one of its branches) becomes blocked. This results in the blood and nutrient supply to the nerve layer of the retina being cut off. This leads to permanent damage and is a common cause of sudden loss of vision in one eye.