1. Sudden impairment of neurological function, especially that resulting from a cerebral hemorrhage; a stroke.
2. A sudden effusion of blood into an organ or tissue.
3. A fit of extreme anger; rage: "The proud ... members suffered collective apoplexy, and this year they are out for blood" (David Finch).
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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