Which word relates to having great size or volume?

The term that relates to having great size or volume is "voluminous." This word specifically describes something that is large in size, bulk, or capacity. In contexts where items or entities are described as voluminous, it often refers to the extent or abundance of something, such as a voluminous book that may contain extensive content or a voluminous cloud that takes up a significant amount of space in the sky. Its usage conveys the idea of considerable quantity or space, making it the most fitting choice for the question about size and volume.

The other terms do not have this connotation. The word "vex" means to annoy or bother, "vilify" refers to speaking ill of someone, and "zealot" indicates a person who is fanatically committed to a cause. None of these terms are associated with the concept of size or volume.