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.
Page last modified: June 14, 2009 Disorders where one eye is higher than the other often cause vertical double vision (diplopia). Common causes include: Disorders where one eye is higher than the other often cause vertical double vision (diplopia). Common causes include: 1  Ocular muscle weakness (called hyper deviation).2  Central ocular control disturbances (here it is called skew).3  Otolithic imbalance (also called skew).hen it occurs even when both eyes are viewing, it is called a hyper deviation. Hyperphoria and hyperdeviation generally refer to the situation where the cause is known. For example, ocular palsies such as 4th nerve palsy can cause a hyper deviation or phoria.