trade dress

Trade dress refers to characteristics of the visual appearance of a product or its packaging (or even the facade of a building such as a restaurant) that may be registered and protected from being used by competitors in the manner of a trademark. These characteristics can include the three-dimensional shape, graphic design, color, or even smell of a product and/or its packaging.
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a product’s design, product packaging, color, or other distinguishing nonfunctional element of appearance

-- see TMEP 1202.02 for more

Context: Trademark 

 the non-functional physical detail and design of a product or its packaging, which indicates or identifies the product's source and distinguishes it from the products of others.

Trade dress includes color schemes, textures, sizes, designs, shapes, and placements of words, graphics, and decorations on a product or its packaging.

A trade dress is non-functional if, taken as a whole, the collection of trade dress elements is not essential to the product's use or does not affect the cost or quality of the product even though certain particular elements of the trade dress may be functional.