What term is used to describe an argument that is logical and well-supported?

The term "valid" is used to describe an argument that is logical and well-supported because it indicates that the reasoning behind the argument is sound and follows a coherent structure. In logical terms, a valid argument ensures that if the premises are true, then the conclusion must also be true. Validity focuses on the internal consistency and the logical flow of the argument rather than the actual truth of the premises.

While "accurate" can denote correctness, and "strong" often refers to an argument that is compelling or impactful, these terms do not specifically capture the idea of logical coherence and sound reasoning in the same way that "valid" does. "Persuasive" refers to the effectiveness of an argument in convincing someone, but it does not necessarily imply that the argument is structured in a logical manner. Thus, "valid" is the best choice for describing an argument that is logical and well-supported.