Which word means inspiring fear or respect due to being impressive in size or capability?

The term "formidable" is used to describe something that instills a sense of fear or respect due to its impressive size, strength, or capability. When you think of something or someone as formidable, it often conveys the idea that they possess qualities that might make them intimidating or awe-inspiring. This is often seen in contexts such as a formidable opponent in sports, a formidable structure in architecture, or even a formidable mind in intellectual discussions. The impact of being formidable is the sum of both respect and fear, demonstrating the dual nature of admiration combined with a healthy acknowledgment of potential challenges.

In contrast, "gaunt" refers to being lean and haggard, often due to suffering or hunger, which does not align with the idea of being impressive. "Foreboding" describes a feeling of impending doom or worry, which isn't related to size or capability. Lastly, "fluster" means to confuse or agitate, which lacks the connotation of respect or fear associated with being impressive. Thus, "formidable" effectively encapsulates the essence of the question, making it the correct choice.