Definition
Aphotic means without light, referring particularly to the deepest parts of the ocean or a body of water where sunlight doesn't penetrate. It's the zone where total darkness reigns, and life has adapted to exist without any light at all. Think of it as the ultimate 'lights-out' environment, far beyond just turning off your bedroom lamp. It's a perpetual night, unlike a simple power outage. Imagine the deepest parts of the ocean, where sunlight never reaches.