gel

1. A semi-solid to almost solid colloid of a solid and a liquid, such as jelly, cheese or opal.
2. Any gel intended for a particular cosmetic use, such as for styling the hair.
3. A film of flexible transparent plastic (such as acetate, celluloid, or cellophane) suitable for making superimpositions or diapositives (image to overlay on other images, especially for overhead projectors); a digital virtual equivalent of this.