“Malignant” vs. “Benign”: Which Is Which?

Although nobody wants to hear that a doctor found a tumor, it’s the word that comes next that makes all of the difference: is it malignant or benign? One of these words has the power to send chills instantly down someone’s spine, while the other can flood a patient with relief.

Let’s take a closer look at which is which.

What does malignant mean?

Malignant is an adjective that’s defined as “disposed to cause harm, suffering, or distress deliberately; feeling or showing ill will or hatred.” It describes something that is very dangerous or harmful in influence or effect.

For example:

  • Turner’s parents did not approve of his new group of friends and feared that they were a malignant crowd that was going to get him into serious trouble.
  • Looking back, Hitler can be considered a malignant tumor spreading dangerous political ideology across the community.

In terms of pathology, malignant means “tending to produce death, and when it comes to tumors specifically, it’s defined as “characterized by uncontrolled growth; cancerous, invasive, or metastatic.”

Malignant was first recorded in English around 1535–45, and it originates from the Latin word malignāre (“to act maliciously”). Synonyms for malignant include spiteful, malevolent, perilous, hurtful, and pernicious.

What does benign mean?

Benign is an adjective that means having a kindly or gracious disposition. Benign can also refer to “showing or expressive of gentleness or kindness” or “favorable; propitious.”

For example:

  • Many consider the Queen of England to be both a stoic yet benign leader and grandmother.
  • As soon as she saw a penny sitting outside of the house, she took it as a benign omen that this was the right home for her family.

When describing the weather, benign means “salubrious; healthful; pleasant or beneficial.” You might say, Instead of the oppressive humidity that has made it feel impossible to breathe, the weather changed to a much more benign and comfortable forecast for the upcoming weekend.

And in terms of pathology, benign means that something is not malignant and instead is self-limiting. For example, when the doctor explained that the lump was benign and not life-threatening, she felt an instant wave relief.

Benign‘s first recorded use was sometime in 1275–1325. The word is ultimately derived from the Latin word benignus (“kind, generous”). Synonyms for benign include good, kindly, benevolent, tender, humane, gentle, and compassionate.

How to use each word

These two words are opposites: benign is the antonym for malignant and you don’t want to mix them up as they have two potentially life-altering meanings:

  • The doctor said that although the pathology report showed malignant cancer, it’s one that is extremely treatable.
  • It turns out she had nothing to worry about, the lump she found was a benign tumor and not the aggressive form of breast cancer that killed her mother.
  • He is incredibly grateful that he went to the doctor when he did, because it turns out he was diagnosed with malignant cancer that would have killed him had he waited any longer for treatment.
  • She can’t explain why she loves watching Dr. Pimple Popper on TLC treat the oversized benign lumps and cysts that make others squirm.

However, it can also be used to describe someone’s demeanor. For example: He first fell in love with her constant grin, her benign eyes, and authentic personality.

Or: She could just tell from the moment she met him that he was malignant and no good was going to come from their relationship.


Avoid those malignant personalities in your life by learning how to identify and describe your most toxic friends.

If you’re looking for more benign topics to read, check out our articles on psychic vs. medium or amicable vs. amiable.


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