Which word refers to something having many aspects?

The term "multifarious" specifically denotes something that is diverse or has many different parts, aspects, or forms. It conveys a sense of variety and complexity, making it an ideal choice for describing something that encompasses multiple dimensions or facets. This word captures the essence of multiplicity, suggesting a richness that goes beyond a singular or uniform characteristic.

In contrast, the other options refer to more limited or singular characteristics. "Monolithic" suggests being massive and uniform, typically lacking variations. "Unidimensional" explicitly means having only one dimension or aspect, while "homogeneous" indicates uniformity or sameness throughout, devoid of diversity. Each of these terms stands in stark contrast to the idea of multiplicity encapsulated by "multifarious." Therefore, "multifarious" is the most fitting choice to describe something with many aspects.