وإما تشبيه مفرد بمركب
And sometimes the subject is single while the comparison term is composite.
The object being explained is one term, yet the image invoked to represent it is a unified arrangement of multiple components. A bright object, for example, may be likened to an entire scene involving light, background and other coordinated details.
The unity of the comparison term is unity of configuration, not necessarily the unity of a physical object. Classification depends on what is imagined and compared rather than word count or superficial grammar.