Osmotic pressure can be defined as the pressure that must be applied to the solution to stop the influx of the solvent (to stop osmosis) through the semipermeable membrane.

Osmosis : The spontaneous flow of solvent particles from a solution of lower concentration in to higher concentration through semi permeable membrane is called osmosis.
Osmotic pressure : The pressure required to prevent the flow of solvent particles from pure solvent into solution through semipermeable membrane is called osmotic pressure.
`{:(pi=(nRT)//V,,”Here “pi=” Osmotic pressure,”,,”V = Volume of solution,”),(“n = No. of moles of solute,”,,”R = Universal gas constant,”,,”T = Absolute temperature”):}`