malignant

adjective ma·lig·nant \ mə-ˈlig-nənt \
Updated on: 17 Nov 2017

Definition of malignant

1 a obsolete :malcontent, disaffected
b :evil in nature, influence, or effect :injurious
  • a powerful and malignant influence
c :passionately and relentlessly malevolent :aggressively malicious
  • the malignant tongues of gossipers
2 :tending to produce death or deterioration
  • malignant malaria
; especially :tending to infiltrate, metastasize, and terminate fatally
  • a malignant tumor

malignantly

adverb

Examples of malignant in a Sentence

  1. a highly malignant form of cancer

  2. a powerful and malignant influence

Recent Examples of malignant from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'malignant.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Origin and Etymology of malignant

Late Latin malignant-, malignans, present participle of malignari


MALIGNANT Defined for English Language Learners

malignant

adjective

Definition of malignant for English Language Learners

  • medical : very serious and dangerous : tending or likely to grow and spread in a rapid and uncontrolled way that can cause death

  • : very evil


MALIGNANT Defined for Kids

malignant

adjective ma·lig·nant \ mə-ˈlig-nənt \

Definition of malignant for Students

2 :likely to cause death :deadly

malignantly

adverb

Medical Dictionary

malignant

adjective ma·lig·nant \ mə-ˈlig-nənt \

medical Definition of malignant

1 :tending to produce death or deterioration
  • malignant malaria
; especially :tending to infiltrate, metastasize, and terminate fatally
  • malignant tumors
— compare benign 1
2 :of unfavorable prognosis :not responding favorably to treatment
  • psychotic reactions with a malignant trend


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