What adjective describes something that is original and highly influential?

The adjective that describes something as original and highly influential is "seminal." This term is often used to refer to works, ideas, or contributions that serve as a foundation for further development in a specific field. A seminal work typically introduces groundbreaking concepts or approaches that significantly impact later thinkers and creators. For example, in literature, a seminal novel might shape the genre and inspire future writers, while in science, a seminal study could influence subsequent research and understanding.

The other terms do not capture the same significance. "Common" refers to something that is widespread and lacks uniqueness or innovation. "Obsolete" describes something that is outdated and no longer in use, which contrasts with the idea of originality. "Trivial" implies something that lacks importance or significance, further distancing it from the meaning of being influential or foundational. Thus, "seminal" accurately conveys the concept of originality and the potential to inspire change or new directions.