A manufacturing plant = a factory= a plant consisting of one or more buildings with facilities for manufacturing
Here are more meanings for the word "plant"
assembly plant - a factory where manufactured parts are assembled into a finished product
auto factory, automobile factory, car factory - a factory where automobiles are manufactured
cannery - a factory where food is canned
chemical plant - an industrial plant where chemicals are produced
closed-circuit television - a television system that is not used for broadcasting but is connected by cables to designated monitors (as in a factory or theater)
conveyer belt, conveyor belt, conveyor, conveyer, transporter - a moving belt that transports objects (as in a factory)
foundry, metalworks - factory where metal castings are produced
lumbermill, sawmill - a mill for dressing logs and lumber
paper mill - a mill where paper is manufactured
industrial plant, plant, works - buildings for carrying on industrial labor; "they built a large plant to manufacture automobiles"
assembly line, production line, line - mechanical system in a factory whereby an article is conveyed through sites at which successive operations are performed on it