sinister
Americanadjective
-
threatening or portending evil, harm, or trouble; ominous.
a sinister remark.
- Synonyms:
- portentous, inauspicious
- Antonyms:
- benign
-
bad, evil, base, or wicked; fell.
his sinister purposes.
-
unfortunate; disastrous; unfavorable.
a sinister accident.
- Synonyms:
- unlucky
- Antonyms:
- favorable
-
of or on the left side; left.
-
Heraldry. noting the side of an escutcheon or achievement of arms that is to the left of the bearer (opposed to dexter).
adjective
-
threatening or suggesting evil or harm; ominous
a sinister glance
-
evil or treacherous, esp in a mysterious way
-
(usually postpositive) heraldry of, on, or starting from the left side from the bearer's point of view and therefore on the spectator's right
-
archaic located on the left side
-
archaic (of signs, omens, etc) unfavourable
Other Word Forms
Etymology
Origin of sinister
First recorded in 1375–1425; late Middle English, from Latin: “on the left hand or side,” hence, “unfavorable, injurious”
Explanation
People who are left-handed might feel unlucky having to use a desk designed for right-handers, but there probably wasn't any sinister, or evil, intent behind the design. Or was there? In the 15th century, when the word sinister came into use in English, people who were left-handed were thought to be bad luck or even evil. In his play Hamlet, Shakespeare wrote of the villain holding a human skull in his sinister — i.e., left — hand. It would seem to be sinister, or wicked, enough to see a human skull in the right hand, not to mention unlucky for the person missing a head in the first place.
Vocabulary lists containing sinister
The SAT: Words to Capture Tone, List 3
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"The Monkey's Paw" by W. W. Jacobs
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The New SAT: Words to Capture Tone
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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.
While the race organizer confirmed they treated runners for dehydration and overheating, some online have speculated that something more sinister could be the cause of the illnesses.
From Los Angeles Times ● Nov. 10, 2026
But something more sinister, he soon discovers, is afoot.
From The Wall Street Journal ● Oct. 30, 2026
Based on the beloved Capcom video game, "Street Fighter" follows super-powered martial artists competing in a global tournament who uncover and battle a sinister conspiracy.
From Barron's ● Oct. 25, 2026
Then, Meta wants everyone to play with its new A.I. model but is the cuteness covering up something sinister?
From Slate ● Oct. 17, 2026
Even the most amateur propagandist could conjure sinister implications.
From "Zeitoun" by Dave Eggers
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Get a wordDefinitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
