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
Glioblastoma is the most common type of malignant brain tumor.
—
Jon Hamilton, NPR, 25 Mar. 2025
Love's death was announced by her family on Sunday, March 23, in a post on X. Love, the first Black Republican woman elected to Congress, was diagnosed with glioblastoma, a malignant brain tumor, in 2022.
—Meredith Kile, People.com, 24 Mar. 2025
Johnston's official diagnosis was a malignant paraganglioma that had spread through her lymph nodes.
—Zoey Lyttle, People.com, 18 Mar. 2025
The spirit of caste is malignant and dangerous everywhere.
—Margie Burns, The Conversation, 17 Mar. 2025
See All Example Sentences for malignant
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Jon Hamilton, NPR, 25 Mar. 2025
Love's death was announced by her family on Sunday, March 23, in a post on X. Love, the first Black Republican woman elected to Congress, was diagnosed with glioblastoma, a malignant brain tumor, in 2022.
—Meredith Kile, People.com, 24 Mar. 2025
Johnston's official diagnosis was a malignant paraganglioma that had spread through her lymph nodes.
—Zoey Lyttle, People.com, 18 Mar. 2025
The spirit of caste is malignant and dangerous everywhere.
—Margie Burns, The Conversation, 17 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 2 Apr. 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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