impressio


impression

 [im-presh´un] 1. a slight indentation or depression, as one produced in the surface of one organ by pressure exerted by another.2. a negative imprint of an object made in some plastic material that later solidifies.3. an effect produced upon the mind, body, or senses by some external stimulus or agent.basilar impression 1. platybasia.2. basilar invagination.

im·pres·sion

(im-presh'ŭn), 1. A mark seemingly made by pressure of one structure or organ on another, seen especially during cadaveric dissections. See also groove for the various impressions of the lungs, for example, descending aorta, subclavian artery, and vena cava. Synonym(s): impressio [TA]2. An effect produced on the mind by some external objects acting through the organs of sense. Synonym(s): mental impression3. An imprint or negative likeness; especially, the negative form of the teeth and/or other tissues of the oral cavity, made in a plastic material that becomes relatively hard or set while in contact with these tissues, made to reproduce a positive form or cast of the recorded tissues; classified, according to the materials of which they are made, as reversible and irreversible hydrocolloid impression, modeling plastic impression, plaster impression, and wax impression. [L. impressio, fr. im- primo, pp. -pressus, to press upon]

im·pres·sion

(im-presh'ŭn) 1. A mark seemingly made by the pressure of one structure or organ on another, seen especially in cadaveric dissections. See also groove for the various impressions of the lungs, e.g., descending aorta, subclavian artery, and vena cava.2. An effect produced on the mind by some external object acting through the organs of sense. 3. An imprint or negative likeness; especially, the negative form of the teeth and/or other tissues of the oral cavity, made in a plastic material that becomes relatively hard or set while in contact with these tissues, made to reproduce a positive form or cast of the recorded tissues; classified, according to the materials of which they are made, as reversible and irreversible hydrocolloid impression, modeling elastic gel impression, plaster impression, and wax impression.
Synonym(s): impressio [TA] . [L. impressio, fr. im- primo, pp. -pressus, to press upon]