a. Suggesting or threatening harm or evil: a sinister smile.
b. Causing or intending harm or evil; wicked: a sinister conspiracy.
a. Portending misfortune or disaster; ominous: sinister storm clouds.
b. Attended by or causing misfortune or disaster: "The day has passed without any sinister accident" (John Quincy Adams).
a. Archaic On the left side; left.
b. Heraldry Situated on or being the side of a shield on the wearer's left and the observer's right.
[Middle English sinistre, unfavorable, from Old French, from Latin sinister, on the left, unlucky.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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