Can someone simply explain what hyponatremia is

Hyponatremia refers to a lower-than-normal level of sodium in the blood. Hyponatremia has sometimes been referred to as "water intoxication".

Answer: hyponatremia

Explanation:

Hyponatremia is a low sodium concentration in the blood. It is generally defined as a sodium concentration of less than 135 mmol/L (135 mEq/L), with severe hyponatremia being below 120 mEq/L. Symptoms can be absent, mild or severe ... Severe symptoms include confusion, seizures, and coma.