Definitions

1. adjective

Having the same concentration of solute as another solution, often in reference to blood or bodily fluids.

“The doctor checked the patient’s blood for isotonic levels to determine the effectiveness of the treatment.”

2. adjective

Having the same osmotic pressure as another solution.

“The isotonic saline solution was used to treat the burn victim.”

3. noun

A solution that has the same osmotic pressure as another solution.

“The isotonic solution was used to test the osmotic balance of the cell.”