In Metropolis (1927), the robot whose appearance is copied by Maria is Machine Man.
The robot is an artificial human created by the inventor Rotwang. In the film’s German production design, it is called the Maschinenmensch, a term that literally means “machine-human.” English-language references commonly call the figure the Machine Man or the Robot.
Rotwang uses the robot as part of a plan involving the city’s ruling class and the workers below. The machine is transformed to resemble Maria, the compassionate mediator who speaks to the workers. This allows the false Maria to manipulate both social groups and intensify the city’s conflict.
A common mix-up is treating “Robot Maria” as the robot’s original name. Maria is the human character whose likeness the machine adopts; the robot itself is the Machine Man. The design became one of cinema’s most influential images of artificial life.