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Noun 1. Plural form of Latin os, the mouth or openings, especially of the cervix. ( 2. An edge or margin. (

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Ora serrata

Noun, pl. orae serratae 1. The serrated junction between the retina and the ciliary body. This junction marks the transition from the simple non-photosensitive area of the retina to the complex, multi-layered photosensitive region. In animals in which the region does not have a serrated appearance, it is called the ora ciliaris retinae. ( 2. The serrated extremity of the optic part of the retina, located a little behind the ciliary body and marking the limits of the percipient portion of the membrane. ( 3. The dentate border of the retina. ( Word origin: From Latin words ora, “margin,” and serra,...

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/ˈôrəl/ Adjective 1. Relating to the mouth; mouthly. ( 2. Pertaining to the mouth, taken through or applied in the mouth, as an oral medication or an oral thermometer. ( 3. Spoken rather than written. ( 4. a. Of, relating to, or characterized by the first stage of psychosexual development in psychoanalytic theory during which libidinal gratification is derived from intake (as of food), by sucking, and later by biting. ( b. A stage in psychosexual development when the child’s interest is concentrated in the mouth; fixation at this stage is said to result in dependence, selfishness, and aggression. ( 5. Of, relating to, or characterized by personality traits of passive dependence and aggressiveness. ( Word origin: From Late Latin oralis, from Latin os (genitive oris) “mouth, opening, face,...

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/ˈôrbit/ Noun, plural orbits 1. A circular or elliptical path of one object around another object. ( 2. A sphere of influence; an area of control. ( 3. The course of one’s usual progression, or the extent of one’s typical range. ( (Anatomy) 1. The bony cavity containing the eyeball; the eye socket. ( 2. The bony cavity perforated for the passage of nerves and blood vessels that occupies the lateral front of the skull immediately beneath the frontal bone on each side and encloses and protects the eye and its appendages. ( Syn: eye socket, orbital cavity, cranial orbit (Physics) 1. The path an electron takes around an atom’s nucleus. ( (Mathematics) 1. A collection of points related by the evolution function of a dynamical system. ( Verb 1. Move in an orbit Word origin: From Old French orbite or directly from Medieval Latin orbita, transferred use of Latin orbita “wheel track, beaten path, rut, course,...

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/ˈôrgən/ Noun, pl. organs (Biology) 1. A collection of tissues joined in a structural unit to serve a common function. ( 2. A part of an organism that is typically self-contained and has a specific vital function, such as the heart or liver in humans. (Google Dictionary) Word origin: The meaning “body part adapted to a certain function” is attested from late 14c., from a Medieval Latin sense of Latin...

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