An imitation.
A comic who does impressions.
An entity that mimics another entity, such as a disease that resembles another disease in its signs and symptoms; see the great imitator.
A mime.
Imitative; characterized by resemblance to other forms; applied to crystals which by twinning resemble simple forms of a higher grade of symmetry.
Pertaining to mimicry; imitative.
Mock, pretended.
To imitate, especially in order to ridicule.
To take on the appearance of another, for protection or camouflage.