PELLICLE

[pel.li.cle] n [MF pellicule, fr. ML pellicula, fr. L, dim. of pellis] (1541): a thin skin or film: as a: an outer membrane of some protozoans (as euglenoids or paramecia) b: a film that reflects a part of the light falling upon it and transmits the rest and that is used for dividing a beam of light (as in a photographic device)