noun

• (military) The use of natural or artificial material on personnel, objects, or tactical positions with the aim of confusing, misleading, or evading the enemy.
• (textiles) A pattern on clothing consisting of irregularly shaped patches that are either greenish/brownish, brownish/whitish, or bluish/whitish, as used by ground combat forces.
• (biology) The resemblance of an organism to its surroundings for avoiding detection.
  "Earless ghost swift moths become “invisible” to echolocating bats by forming mating clusters close[…]above vegetation and effectively blending into the clutter of echoes that the bat receives from the leaves and stems around them. Many insects probably use this strategy, which is a close analogy to crypsis in the visible world—camouflage and other methods for blending into one’s visual background."

verb

• (transitive) To hide or disguise something by covering it up or changing its appearance.
  "THE CONCISE ENCYCLOPAEDIA OF WORLD RAILWAY LOCOMOTIVES. Edited by P. Ransome-Wallis. Hutchinson. 50s. A gaudy jacket, remarkably out of keeping with the contents, camouflages the weightiest and meatiest work on a railway topic since the war."