hypotonic

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1. Pathology. Having less than normal tone or tension, as of muscles or arteries.
2. Chemistry. Having the lower osmotic pressure of two fluids.

A solution more dilute than the body fluids, see isotonic.

Exhibiting less tension or firmness.

1. Applied to an external fluid which causes cells to increase in volume.

2. Applied to sports drinks that have a salt concentration less than that of the body fluids.

3. Applied to conditions below normal tension or tone.

1. having an abnormally reduced tonicity or tension.
2. having an osmotic pressure lower than that of the solution with which it is compared.

• h. dehydration — occurs when there is secretory loss of sodium from the intestinal epithelium, e.g. salmonellosis, in osmolar excess of the concurrent fluid loss. See also dehydration.