osmosis
diffusion of water through a semi-permeable membrane from a region of higher water potential (lower salt concentration) to a region of lower water potential (higher salt concentration).
osmotic pressure
pressure generated by the movement of water across the cell membrane caused by the difference between solute concentrations on each side.
outriggers
projecting or extendible structures used for stabilization on aerial devices. cranes. and other vehicles that support elevated or outstretched loads.