Osmoresistant refers to a substance or organism's ability to resist osmotic pressure, the pressure that results from differences in solute concentration between two solutions separated by a semi-permeable membrane. Some synonyms for osmoresistant include osmotolerant, halotolerant, and halophilic. Osmotolerant refers to organisms or materials that can withstand high solute concentrations, while halotolerant specifically refers to organisms that can survive in high salt concentrations. Halophilic refers to organisms that require high salt concentrations for growth and metabolism. Other related terms include osmoregulation, the process by which organisms maintain internal solute concentrations, and osmoprotectants, molecules that prevent damage to cells from high osmotic pressures.