Cuttlefish brown

Quick answer：

Cuttlefish brown refers to the color of the brown ink used by cuttlefish for defense and camouflage. Cuttlefish are cephalopods known for their ability to change color rapidly to blend with their surroundings. The brown ink is a dense, dark substance that can confuse predators and allow the cuttlefish to escape. This ink is produced from a specialized gland located in the cuttlefish's rear end.