What does it mean if a person is described as "devoid of intelligence"?

Describing a person as "devoid of intelligence" indicates that they lack understanding, insight, or the ability to think critically. The term "fatuous" is the most fitting choice here because it describes someone who is complacently foolish, lacking in seriousness or intelligence, and often exhibiting a kind of shallow thinking that aligns well with being devoid of intelligence.

The other words do not convey the same meaning. "Expunge" refers to erasing or removing completely, which does not relate to intelligence. "Excise" similarly means to cut out or remove, typically used in a different context. "Expediency," on the other hand, pertains to the quality of being convenient and practical, often to the point of being immoral or improper, which does not describe a person's intelligence. Thus, "fatuous" effectively captures the essence of lacking intelligence in a person.