In this title the following words have the meanings indicated. “Commodity in bulk” means the sale of a commodity when the quantity is determined at the time of sale. “Commodity in package form” means a commodity packaged before sale in any manner including barrels, bags, sacks, cartons, or any other container constituting a unit quantity of the commodity, for either wholesale or retail use. Any individual item or lot of any commodity on which there is marked a selling price based on an established price per unit of weight or measure shall be considered a commodity in package form. “Cord”, when used in connection with wood intended for any purpose, means the amount of wood contained in a space of 128 cubic feet, when the wood is ranked and well stowed. “Package” means commodity in package form. “Primary standards” means the physical standards of the State which serve as the legal reference from which all other standards and weights and measures are derived. “Sale in bulk” means the sale of a commodity when the quantity is determined at the time of sale. “Secondary standards” means the physical standards traceable to the primary standard through acceptable laboratory comparisons and used in enforcing weights and measures laws and rules and regulations. “Sell” means barter and exchange. “Shellfish” means any edible, aquatic, invertebrate animal having a shell. “Weight” means net weight as used in this subtitle. “Weight and measure” means any instrument or device used for weighing or measuring, and any appliance or accessory associated with any instrument or device used for weighing or measuring.