When you need water in your body what is it called?

When your body needs water, it is referred to as dehydration. Dehydration occurs when the body loses more fluids than it takes in, leading to a deficiency in water that can affect various bodily functions. Signs of dehydration can include thirst, dry mouth, fatigue, and reduced urine output. It's essential to replenish fluids to maintain proper hydration and overall health.