From DR. BOLI’S UNABRIDGED DICTIONARY.

Natural (adjective).—1. Of food, cosmetics, etc.: Packaged in materials made from petroleum by-products and processed into standardized units from ingredients ultimately derived from substances present in the physical universe.

2. Of art, literature, etc.: Conforming to the current clichés that define what is correct in representational art, as opposed to the clichés of the era immediately past, which are designated artificial.