What Does It Mean?

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From our dictionary:
vac•u•ous

(vak'yOO-us)
adj.
1. without contents; empty: the vacuous air.
2. lacking in ideas or intelligence: a vacuous mind.
3. expressing or characterized by a lack of ideas or intelligence; inane; stupid: a vacuous book.
4. purposeless; idle: a vacuous way of life.