- without contents; empty: the vacuous air.
- lacking in ideas or intelligence: a vacuous mind.
- expressing or characterized by a lack of ideas or intelligence; inane; stupid: a vacuous book.
- purposeless; idle: a vacuous way of life.
- containing nothing; empty
- bereft of ideas or intelligence; mindless
- characterized by or resulting from vacancy of mind
- indulging in no useful mental or physical activity; idle
- (of an operator or expression) having no import; idle: in (x) (John is tall) the quantifier (x) is vacuous
