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adjective be·nign \bi-ˈnīn\

Simple Definition of benign

  • medical : not causing death or serious injury

  • : without cancer : not cancerous

  • : not causing harm or damage

Source: Merriam-Webster's Learner's Dictionary

Full Definition of benign

  1. 1 :  of a gentle disposition :  gracious <a benign teacher>

  2. 2 a :  showing kindness and gentleness <benign faces> b :  favorable, wholesome <a benign climate>

  3. 3 a :  of a mild type or character that does not threaten health or life; especially :  not becoming cancerous <a benign lung tumor> b :  having no significant effect :  harmless <environmentally benign>

benignity play \-ˈnig-nə-tē\ noun
benignly play \-ˈnīn-lē\ adverb

Examples of benign in a sentence

  1. … substituting such benign power sources as the hybrid, the fuel cell, and the electric motor in place of … the internal-combustion engine. —Brock Yates, Car and Driver, May 2000

  2. Rather than a benign fairytale creature that delivers babies, the marabou stork is an ugly, viciously predatory African bird that preys on flamingos … —James Polk, New York Times Book Review, 11 Feb. 1996

  3. … her pulled-back black hair had gone gray in strange distinct bands, but she seemed much as he remembered her, solid and energetic, with a certain benign defiance. —John Updike, New Yorker, 23 May 1988

  4. When she chose to smile on me, I always wanted to thank her. The action was so graceful and inclusively benign. —Maya Angelou, I Know Why the Caged Bird Sings, 1969

  5. We were happy to hear that the tumor was benign.

  6. <around campus he's known as a real character, but one whose eccentricities are entirely benign>

Origin of benign

Middle English benigne, from Anglo-French, from Latin benignus, from bene + gignere to beget — more at kin

First Known Use: 14th century

BENIGN Defined for Kids


adjective be·nign \bi-ˈnīn\

Definition of benign for Students

  1. 1 :  marked by gentleness and kindness <a benign ruler> <a benign mood>

  2. 2 :  not causing death or serious harm <a benign growth on the skin>

benignly adverb <nodded benignly>

Medical Dictionary


adjective be·nign \bi-ˈnīn\

Medical Definition of benign

  1. 1:  of a mild type or character that does not threaten health or life <benign malaria> <a benign liver cyst>; especially :  not becoming cancerous <a benign lung tumor>—compare malignant 1

  2. 2:  having a good prognosis :  responding favorably to treatment <a benign psychosis>

Seen and Heard

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to expose to danger or risk

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