mimicry

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The act, practice, or art of mimicking.
2. n. An instance of mimicking.
3. n. Biology The resemblance of one organism to another or to an object in its surroundings for concealment and protection from predators.

Century Dictionary and Cyclopedia

1. n. The act of imitating in speech, manner, or appearance; mockery by imitation; simulation.
2. n. An imitation; that which imitates or simulates.
3. n. In zoology, the simulation of something else in form or color, etc.; mimesis. Commonly called protective mimicry, from the immunity secured by such resemblance, as when the insect known as the walking-stick simulates a dead twig of a tree, when abutterfly assimilates in color to that of the flowers upon which it habitually feeds, or a bird's nest is so constructed as to resemble a bunch of moss on a bough, etc. Also mimetism.

Wiktionary

1. n. The act or ability to simulate the appearance of someone or something else.

GNU Webster's 1913

1. n. The act or practice of one who mimics; ludicrous imitation for sport or ridicule.
2. n. Protective resemblance; the resemblance which certain animals and plants exhibit to other animals and plants or to the natural objects among which they live, -- a characteristic which serves as their chief means of protection against enemies; imitation; mimesis; mimetism.

WordNet 3.0

1. n. the resemblance of an animal species to another species or to natural objects; provides concealment and protection from predators
2. n. the act of mimicking; imitative behavior