The term that describes the environment inside the cell is hypotonic.
Hypotonic environment is a solution that has a reduced osmotic pressure than a certain fluid, usually a body fluid. In a hypotonic solution, all the dissolved solute molecules have a molar concentration that is lower than that of another solution or a cell. When a cell is exposed to a hypotonic environment, there is movement of water into the cell and the cell may burst if it does not have a cell wall.