No, an API is not a translator. To go back to my earlier analogy: When you're reading this post, your brain is interpreting the English that I have written - the English language itself isn't translating it for you. In the same way, a GPU driver can interpret e.g. OpenGL commands - there isn't necessarily an independent "OpenGL API software" that runs on your computer and translates commands. If both a game and the GPU driver know how to speak OpenGL, they don't need a translator in between them.
(Fun fact, though: It is possible to make translators between two different APIs. For instance, https://en.wikipedia.org/wiki/ANGLE_(software) translates OpenGL to Direct3D. Do note that such a translator can implement an API (instead of the GPU driver implementing it directly) but can't be an API.)
(Fun fact, though: It is possible to make translators between two different APIs. For instance, https://en.wikipedia.org/wiki/ANGLE_(software) translates OpenGL to Direct3D. Do note that such a translator can implement an API (instead of the GPU driver implementing it directly) but can't be an API.)