From Middle French malignant, from Late Latin malignans. See malign.

• IPA^(key): /məˈlɪɡnənt/

• Audio (US):

  (file)

malignant (comparative more malignant, superlative most malignant)

1. Harmful, malevolent, injurious.

   malignant temper;  malignant revenge;  malignant infection

   • 1863 August 26, Abraham Lincoln, Letter to James Conkling‎^[1], page 7:

     […]while, I fear, there will be some white ones, unable to forget that, with malignant heart, and deceitful speech, they have strove to hinder it.

2. (medicine) Tending to produce death; threatening a fatal issue.

   Antonyms: benign, non-malignant

   malignant diphtheria

   a malignant tumor

   • 1921, Ben Travers, chapter 1, in A Cuckoo in the Nest, Garden City, N.Y.: Doubleday, Page & Company, published 1925, →OCLC:

     “[…] the awfully hearty sort of Christmas cards that people do send to other people that they don't know at all well. You know. The kind that have mottoes[…]. And then, when you see [the senders], you probably find that they are the most melancholy old folk with malignant diseases. […]”

• malign

malignant (plural malignants)

1. A deviant; a person who is hostile or destructive to society.
   • 1823, The Retrospective Review, volume 7, page 11:

     As devout Stephen was carried to his burial by devout men, so is it just and equal that malignants should carry malignants […]

   • 1999, National Institute of Business Management, Difficult People at Work, →ISBN, page 8:

     A malignant in a position of real power immediately becomes a tyrant.

2. (historical, derogatory, obsolete) A person who fought for Charles I in the English Civil War.

malignant

1. third-person plural present active indicative of malignō