plate: see electron tube.

Plate, River: see Plata, Río de la.

Theory that the Earth's lithosphere (the crust and upper portion of the mantle) is divided into about 12 large plates and several small ones that float on and travel independently over the asthenosphere. The theory revolutionized the geological sciences in the 1960s by combining the earlier idea of continental drift and the new concept of seafloor spreading into a coherent whole. Each plate consists of rigid rock created by upwelling magma at oceanic ridges, where plates diverge. Where two plates converge, a subduction zone forms, in which one plate is forced under another and into the Earth's mantle. The majority of the earthquakes and volcanoes on the Earth's surface occur along the margins of tectonic plates. The interior of a plate moves as a rigid body, with only minor flexing, few earthquakes, and relatively little volcanic activity.

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Terminal or electrode from which electrons leave a system. In a battery or other source of direct current, the anode is the negative terminal. In a passive load it is the positive terminal. In an electron tube, electrons from the cathode travel across the tube toward the anode; in an electroplating cell, negative ions are deposited at the anode.

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Articles made of copper coated with silver by fusion. The technique was discovered circa 1742 by the Sheffield (Yorkshire, Eng.) cutler Thomas Boulsover, who noted that the combination of fused silver and copper retained the ductility of both metals and acted as one when manipulated. Other workshops in Britain, continental Europe, and North America also produced cooking and eating utensils of Sheffield plate. After the introduction of electroplating in 1840, production of Sheffield plate declined; by the 1870s it had all but disappeared. Admired for its soft, glowing gray lustre, Sheffield-plate ware soon came to be prized and collected.

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Plate may refer to:

• Plate (dishware)
• Plate (structures), a type of foundation
• A flat piece of metal used in orthopedics to connect the two parts of a broken bone, such as a dynamic compression plate
• Plate armor, body armor made of metal plates
• Plate electrode, part of a vacuum tube
• Home plate, a piece of equipment in baseball
• Photographic plate, a type of film
• Printing plate, in lithography
• A lithograph bound into a book, especially when the book is otherwise letterpress printed
• River Plate, a river in Uruguay and Argentina
• Steel plate, sheet metal in a thicker form
• Tectonic plate, in geology
• Vehicle registration plate
• A sub-class of Culture GSV
• Theoretical plate in separation processes
• Appendages of dinosaurs of the infraorders Stegosauria and Ankylosauria
• Roundel argent, in British heraldry
• Sterling silver cutlery and dishware
• Plating
• Wall plate - horizontal structural elements at the top and bottom of a wall in platform framing building construction methodology.
• Wall plates are variously described as prefaced by the words: Sill, top, bottom, ceiling, floor, or base.

• Tourelle de la Plate, a lighthouse in France,
• Club Atlético River Plate, an Argentine football club based in Buenos Aires
• Christina Plate (1965-), German actress
• Plate, Germany, a municipality in Mecklenburg-Vorpommern, Germany
• Weightlifting slang for a 45lbs. or 20 kg. weight used on a barbell.