What is camouflage?

In military terms, camouflage means disguising people and objects so that they blend into their surroundings and are more difficult to detect. In this, the military are merely copying nature. A zebra's or a tiger's stripes make it hard for other animals to see them amidst the tall grass. Frogs, lizards and snakes are marked in ways that enable them to merge into whatever background is their natural habitat. Some animals change their coats seasonally. Stoats are brown in summer and white to blend into the snow in winter, when they are called ermine.
The cleverest form of camouflage is the one called mimicry, in which one animal is marked like another. The viceroy butterfly resembles the monarch butterfly because birds find the monarch repugnant and so the viceroys can fly about more safely.

(My Book of Questions and Answers, Ref: 083, England: Peter Haddock Publishing)