Which word means to get in the way of or hinder progress?

The term "inhibit" means to obstruct or hinder progress, making it the correct choice in this context. In various scenarios—whether discussing personal growth, scientific processes, or technological advancements—something that inhibits can stall or prevent forward movement or development. This concept is widely utilized in discussions about health, psychology, and even social interactions where certain factors may limit the ability to achieve goals or maximize potential.

In contrast, the other choices reflect different meanings. "Vigorous" refers to something done with force or energy but does not imply any form of obstruction. "Propellant" pertains to a substance used to propel something, typically in a mechanical or scientific context, and is unrelated to hindering progress. "Cordially" means in a warm and friendly manner, lacking any connotation of obstruction or limitation. Thus, "inhibit" stands out as the appropriate word that aligns with the definition of hindering progress.