Technically the US is a form of democracy. It is a type of representative, or indirect, democracy.

It is not direct democracy, which is also called a pure democracy, with the best known example being James Madison in Federalist 10.

See https://en.wikipedia.org/wiki/Types_of_democracy for a list of some of the types of democracy. It does not list a "true democracy". I suspect that you meant to use "pure" instead of "true" in your comment.