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Synonyms

dastardly

American  
[das-terd-lee] / ˈdæs tərd li /

adjective

  1. cowardly; meanly base; sneaking.

    a dastardly act.


dastardly British  
/ ˈdæstədlɪ /

adjective

  1. mean and cowardly

"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

Other Word Forms

  • dastardliness noun

Etymology

Origin of dastardly

First recorded in 1560–70; dastard + -ly

Explanation

Someone who's dastardly is a scoundrel or a cowardly villain. A superhero might try to protect a city from a dastardly criminal mastermind. Use the adjective dastardly to describe a person or action that's underhanded and mean. Criminals, pirates, and bullies are all frequently called dastardly. An unprovoked military strike is also sometimes described as dastardly, referencing President Franklin Roosevelt's famous 1941 speech after the Japanese attack on Pearl Harbor, which he called an "unprovoked and dastardly attack by Japan." In the 1500s, dastardly meant "dull," from the now-obsolete dastard, "one who is lazy or dull."

Keep Reading on Vocabulary.com

Vocabulary lists containing dastardly

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.

The 7th District, which looks like a scorpion, is appropriately dastardly, stretching from mountainous country in the western part of the state straight to expressways over the Potomac River into Washington D.C.

From Slate • Apr. 22, 2026

“How devastating it would be that the community is coming together after the fires and they are scared away because of some dastardly act,” Cunin said.

From Los Angeles Times • Dec. 14, 2025

The Grossman Law Firm, which has offices in Southern California, outlines the reasons and means for removing a dastardly trustee such as your brother.

From MarketWatch • Nov. 11, 2025

Joined by his wife Katie, he plunges into another assignment, as he tries to get the "spirit of Christmas" back from the dastardly humbugs.

From BBC • Nov. 13, 2024

That dastardly cat had lurked in the shadows by the door.

From "Secrets at Sea" by Richard Peck