Vacuous means empty of thought or meaning. A vacuous smile, vacuous remarks, vacuous celebrity culture.
It is a harsher word than empty because it accuses: a vacuous statement is one that sounded like something and was not. In logic it has a technical use, where a vacuous truth holds only because nothing meets the condition.
1adjectivevacuousEmpty of thought or meaning.
“The celebrity gave a vacuous interview full of smiles and empty phrases.”
vacuous is a quality.
Latin vacuus means empty, the root of vacuum and vacant.
Proto-Indo-European
*h₁weh₂-
Latin
vacuus — empty, vacant
English, today
vacuous
Latin vacuus (“empty, vacant”) ous.
Etymology from Wiktionary, CC BY-SA