1. Showing a lack of intelligence or thought; stupid and silly
   - asinine, fatuous, inane, mindless 
2. Devoid of significance or point
   "vacuous comments"
   - empty, hollow 
3. Devoid of matter
   "a vacuous space" 
4. Void of expression
   - blank

See also: empty, foolish, incommunicative, meaningless, nonmeaningful, uncommunicative, vacuity, vacuously, vacuousness

Encyclopedia: Vacuous

• kitchen help
• kitchen island
• kitchen match
• kitchen midden
• kitchen police
• kitchen range
• kitchen sink
• kitchen stove
• kitchen table
• kitchen utensil
• Kitchener
• kitchenette
• kitchenware
• field bean
• field bindweed
• field brome
• field capacity
• field chamomile
• field chickweed
• field coil
• field corn
• field cricket
• field day
• field emission
• field event