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adjective vac·u·ous \ˈva-kyə-wəs\

Simple Definition of vacuous

  • : having or showing a lack of intelligence or serious thought : lacking meaning, importance, or substance

Source: Merriam-Webster's Learner's Dictionary

Full Definition of vacuous

  1. 1 :  emptied of or lacking content

  2. 2 :  marked by lack of ideas or intelligence :  stupid, inane <a vacuous mind> <a vacuous movie>

  3. 3 :  devoid of serious occupation :  idle

vacuously adverb
vacuousness noun

Examples of vacuous in a sentence

  1. a dull and vacuous movie

  2. He had a vacuous expression on his face.

Did You Know?

As you might have guessed, "vacuous" shares the same root as "vacuum"-the Latin adjective vacuus, meaning "empty." This root also gave us the noun "vacuity" (the oldest meaning of which is "an empty space") as well as the verb "evacuate" (originally meaning "to empty of contents"). Its predecessor, the verb "vacare," is also an ancestor of the words "vacation" and "vacancy" as well as "void." All of these words suggest an emptiness of space, or else a fleeing of people or things from one place to another. "Vacuous" appeared in English in the middle of the 17th century, at first literally describing something that was empty. It acquired its figurative usage, describing one who is lacking any substance of the mind, in the mid-1800s.

Origin of vacuous

Latin vacuus

First Known Use: circa 1660

Synonym Discussion of vacuous

empty, vacant, blank, void, vacuous mean lacking contents which could or should be present. empty suggests a complete absence of contents <an empty bucket>. vacant suggests an absence of appropriate contents or occupants <a vacant apartment>. blank stresses the absence of any significant, relieving, or intelligible features on a surface <a blank wall>. void suggests absolute emptiness as far as the mind or senses can determine <a statement void of meaning>. vacuous suggests the emptiness of a vacuum and especially the lack of intelligence or significance <a vacuous facial expression>.

Seen and Heard

What made you want to look up vacuous? Please tell us where you read or heard it (including the quote, if possible).


to manage or play awkwardly

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