means A series of still images shown in rapid succession to create the illusion of motion, captured on a strip of light-sensitive material — or, more broadly, the movie itself and the medium that delivers it.

from From Old English 'filmen,' meaning a thin skin or membrane — the kind that forms on milk or covers an eye. The word kept that sense of a delicate coating for centuries, which is why a fine layer of dust or grease is still called a film. When photographers in the 19th century needed a name for the thin, light-sensitive coating spread over their plates and strips, the old word for 'membrane' was waiting. From the physical strip, the name leapt to the whole art form.