means A prototype is the first working version of something, built to test an idea before you commit to making the real, polished thing.

from From Greek prōtotypon, 'original, primitive form,' built from prōtos 'first' (the same 'proto-' that fronts protozoa and protagonist) and typos 'impression, model, type' — literally a thing struck or stamped as a pattern. It entered English in the early 17th century by way of Latin prototypus, meaning the original model from which copies are taken.