Read the dictionary definition of grid. All definitions for this word.
1. a cooking utensil of parallel metal bars; used to grill fish or meat
2. an electrode placed between the cathode and anode of a vacuum tube to control the flow of electrons through the tube
3. a perforated or corrugated metal plate used in a storage battery as a conductor and support for the active material
4. a system of high tension cables by which electrical power is distributed throughout a region
5. a pattern of regularly spaced horizontal and vertical lines
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Merriam-Webster definition of grid