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Synonyms

suspicious

American  
[suh-spish-uhs] / səˈspɪʃ əs /

adjective

  1. tending to cause or excite suspicion; questionable.

    suspicious behavior.

    Synonyms:
    doubtful, dubious, suspect
  2. inclined to suspect, especially inclined to suspect evil; distrustful.

    a suspicious tyrant.

    Synonyms:
    wary, mistrustful
  3. full of or feeling suspicion.

  4. expressing or indicating suspicion.

    a suspicious glance.


suspicious British  
/ səˈspɪʃəs /

adjective

  1. exciting or liable to excite suspicion; questionable

  2. disposed to suspect something wrong

  3. indicative or expressive of suspicion

"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

Usage

What does suspicious mean? To be suspicious is to have a suspicion about someone or something, especially to have a feeling of distrust about the person or thing. To be suspicious of someone most often involves suspecting that they are engaged in some wrongdoing, as in My parents became suspicious of me when I kept asking whether they’d be home tomorrow. The word is commonly used to describe a person who is suspicious of someone or something in a specific situation. Sometimes, though, it’s used to describe a person who’s suspicious in general—meaning that they’re generally skeptical or distrustful. It can also be used to describe something, such as an action, that indicates that a person is suspicious, as in She gave me a suspicious look that meant she knew I was up to something. Suspicious can also be used to describe someone or something that causes suspicion, as in The guards are trained to identify suspicious people, suspicious behavior, and suspicious packages. Being suspicious is usually based on something, such as a hunch or some kind of evidence, but the word is typically used in situations in which there is some doubt—when someone suspects something, but isn’t sure. The same thing is implied by the verb suspect and the noun suspicion. Suspicious is most commonly used in negative contexts, but this isn’t always the case. For example, you might be suspicious that someone is planning a surprise party for you. Example: Police are encouraging citizens to alert the authorities if they see any suspicious activity on the subway.

Other Word Forms

Etymology

Origin of suspicious

First recorded in 1300–50; Middle English, from Latin suspīciōsus, from suspīci(ō) “mistrust” ( see suspicion) + -ōsus -ous

Explanation

Suspicious behavior inspires distrust. Prancing around your backyard in a trench coat and fake mustache during daylight might elicit weird looks from your neighbors; do it at night, though, so that your silhouette glides past their windows, and what appeared innocent enough hours before will quickly transition to suspicious. Use this adjective to describe a behavior or event that arouses doubt or mistrust. How to avoid appearing suspicious? Well, for one, stop pausing mid-conversation to take covert notes in that little journal of yours. And two, don’t wear sunglasses indoors, and don’t try to walk without making a sound. That will make people cagey, which is a synonym for suspicious. Other synonyms include apprehensive, doubtful, wary, and watchful.

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Vocabulary lists containing suspicious

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.

Officers said investigations were continuing, adding they did not believe there were any suspicious circumstances.

From BBC • May 26, 2026

Polymarket and Kalshi—which allow users to bet on everything from geopolitical events to stock market moves—have made headlines in recent months after a batch of suspicious trades raised concerns of insider trading in Washington.

From The Wall Street Journal • May 26, 2026

And so it’s a bit suspicious that he can’t make his eldest progeny’s wedding.

From Slate • May 23, 2026

Soon after, Girardi grew suspicious of charges being made to her card by a Hollywood costumer — worries she reported to one of Girardi Keese’s clients, an agent in the Secret Service, records show.

From Los Angeles Times • May 22, 2026

I hollered, hopping up from the bed in my bare feet and ready to go call on this suspicious barber.

From "The Detective's Assistant" by Kate Hannigan

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