an exercise in which a person lies flat on the back, lifts the torso to a sitting position, and then lies flat again without changing the position of the legs: formerly done with the legs straight but now usually done with the knees bent.
noun 1. a piece of waterproof fabric or other material carried by campers, hikers, etc., and used for sitting on wet surfaces. 2. Chiefly British Informal. the buttocks.
noun, plural situses, situs. 1. position; situation. 2. the proper or original position, as of a part or organ. noun, Latin. 1. in situ. noun (pl) -tus 1. position or location, esp the usual or right position of an organ or part of the body situs si·tus (sī’təs) n. pl. situs Position, especially normal or […]
[in-vur-suh s] /ɪnˈvɜr səs/ noun, Medicine/Medical. 1. a congenital defect in which an organ is on the side opposite from its normal position. situs inversus situs in·ver·sus (ĭn-vûr’səs) n. A congenital condition in which the organs of the viscera are transposed through the sagittal plane so that the heart, for example, is on the right […]
noun 1. common situs picketing.