Question

What is the best way to describe what “third party” means in American politics?

Answer 1

Any political party that does not agree with the positions of the two major political parties.

Step-by-step explanation:

Answer 2

In electoral politics, a third party is any party contending for votes that failed to outpoll either of its two strongest rivals (or, in the context of an impending election, is considered highly unlikely to do so). ... In the United States of America, there have been numerous "third parties".