What term describes something that inspires fear or respect through being impressively large or powerful?

The term that describes something that inspires fear or respect through being impressively large or powerful is "formidable." This word captures the essence of strong presence or capability that commands attention and respect due to its sheer power or imposing nature. A formidable entity is not only powerful but also presents a challenge or obstacle that is easily recognized due to its significant strength or impact, making it impressive in nature.

The other terms, while they can convey a sense of fear or dominance, do not encapsulate the same level of awe-inspiring presence that "formidable" does. "Intimidating" often relates to the act of causing fear but lacks the emphasis on size or power. "Substantial" refers more to quantity or importance rather than impressiveness. "Overbearing" implies being excessively domineering or controlling, which doesn't necessarily align with the notion of reverence linked with size and power. Therefore, "formidable" is the most fitting term in this context.