edema

meaning in plain English

Swelling in your body caused by extra fluid trapped in your tissues, like when your ankle puffs up after you sprain it.

for example

After sitting on the plane for hours, she noticed edema in her legs and had to walk around to get the blood flowing again.

Imagine pressing your finger into your skin and leaving a dent that stays for a few seconds—that’s what edema feels like, but it doesn’t always go away so quickly. Why does it happen? Because something’s making your body hold onto too much water where it shouldn’t, like a leaky pipe in a wall that keeps the drywall damp.