C3P0 is an Android, right? with humanlike form if not surface color and texture.
R2D2 is a Robot - actually an Astromech.
But in that world just as in ours - terms like Xerox and Kleenex and Q-tip take on a common usage that is larger than the literal meaning - so "droid" in the world of StarWars is slang covering both robots and androids.
And don't forget Cyborgs - and is there a cut off - Luke with his mechanical hand for example - is he a cyborg? part human part...