There are several synonyms that could be used as alternatives for the term "circular plant bakery". One possible option is "round cake factory", which emphasizes the production of baked goods in a round shape. Another option is "circular pastry plant", which specifically highlights the creation of pastries within the bakery. A third synonym could be "roundish bakery facility", which employs a more general term for the type of baked goods produced and the shape of the building. Ultimately, the particular synonym used will depend on the context in which it is being employed and the emphasis that is being placed on various aspects of the bakery's operations.