malignant
adjective
ma·lig·nant
mə-ˈlig-nənt 
1
: tending to produce death or deterioration
malignant malaria
2
a
: evil in nature, influence, or effect : injurious
a powerful and malignant influence
b
: passionately and relentlessly malevolent : aggressively malicious
the malignant tongues of gossipers
c
obsolete
: malcontent, disaffected
malignantly
adverb
Examples of malignant in a Sentence
a highly malignant form of cancer
a powerful and malignant influence
Recent Examples on the Web
Last month, my son reached two years in remission from a rare, malignant cancer that almost took his eye and his life.
—
Dayna Copeland, The Mercury News, 15 Mar. 2025
After a series of tests, Karen was diagnosed with a glioma of the pons, a malignant tumor growing within the middle part of her brain stem.
—Jackie Tempera, People.com, 27 Apr. 2025
In 2024, Tina Knowles, 71, underwent a lumpectomy to have the malignant tumor removed.
—Sara Vallone, Miami Herald, 22 Apr. 2025
Based on breast imaging, AI tools can be used to better predict if a lesion is malignant and support clinical decision making.
—Eyal Shamir, Forbes, 14 Mar. 2025
See All Example Sentences for malignant
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Dayna Copeland, The Mercury News, 15 Mar. 2025
After a series of tests, Karen was diagnosed with a glioma of the pons, a malignant tumor growing within the middle part of her brain stem.
—Jackie Tempera, People.com, 27 Apr. 2025
In 2024, Tina Knowles, 71, underwent a lumpectomy to have the malignant tumor removed.
—Sara Vallone, Miami Herald, 22 Apr. 2025
Based on breast imaging, AI tools can be used to better predict if a lesion is malignant and support clinical decision making.
—Eyal Shamir, Forbes, 14 Mar. 2025
See All Example Sentences for malignant
Cite this Entry
“Malignant.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/malignant. Accessed 27 May. 2025.
Copy CitationKids Definition
malignant
adjective
ma·lig·nant
mə-ˈlig-nənt
1
: evil in influence or effect : injurious
3
: tending to produce death
malignant tumors
malignantly
adverb
Medical Definition
malignant
adjective
ma·lig·nant
mə-ˈlig-nənt
1
: tending to produce death or deterioration
malignant malaria
especially
: tending to infiltrate, metastasize, and terminate fatally
malignant tumors
compare benign sense 1
2
: of unfavorable prognosis : not responding favorably to treatment
psychotic reactions with a malignant trend
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