vac·u·ous
adj.
1. Devoid of matter; empty.
2. a. Lacking intelligence; stupid.
b. Devoid of substance or meaning; inane: a vacuous comment.
c. Devoid of expression; vacant: "The narrow, swinelike eyes were open, no more vacuous in death than they had been in life" Nicholas Proffitt.
3. Lacking serious purpose or occupation; idle. See Synonyms at empty.

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