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Synonyms

clueless

American  
[kloo-lis] / ˈklu lɪs /

adjective

Informal.
  1. ignorant, unaware, or uninformed.

    I remember thinking my mom was clueless when I was a teenager.


clueless British  
/ ˈkluːlɪs /

adjective

  1. slang helpless; stupid

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of clueless

First recorded in 1940–45; clue + -less

Explanation

Someone is clueless if they have no idea what's happening. The unsuspecting victim of a practical joke is usually clueless right up until everyone starts laughing. You could reassure your brother that your mom has no idea you're planning a surprise party by saying, "Don't worry, she's totally clueless." Or you might worry that your friend failed the big geometry test, based on the clueless expression on his face during the exam. In the 1860s, clueless meant "leaving no clues behind," but by 1943 it gained its current meaning, which became even more popular as student slang in the 1980s.

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Vocabulary lists containing clueless

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

Madlanga put it to Magane: "You were clueless, and you knew that you were clueless."

From BBC May 30, 2026

But when it comes to ads that depict Pratt as Batman or Luke Skywalker, he said, “if you don’t know that they’re AI generated, you’re pretty clueless to begin with.”

From Los Angeles Times May 18, 2026

Banks are used to working with the surviving relatives, including those who are clueless or casually dressed.

From Salon Mar. 24, 2026

She said she scanned the table for recording devices, but concluded they were clueless investors as they fumbled through basic questions about Slovenian politics.

From The Wall Street Journal Mar. 23, 2026

Is that what they were talking about in the lunchroom yesterday, when they were so obviously talking about me that even Maya—who can be so clueless about social stuff—felt sorry for me?

From "Auggie & Me" by R. J. Palacio

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