Antonyms of adj benign

3 senses of benign

Sense 1
benign (vs. malignant) -- (not dangerous to health; not recurrent or progressive (especially of a tumor))

malignant (vs. benign) -- (dangerous to health; characterized by progressive and uncontrolled growth (especially of a tumor))
        => cancerous -- (relating to or affected with cancer; "a cancerous growth")

Sense 2
benign (vs. malign), benignant -- (pleasant and beneficial in nature or influence; "a benign smile"; "the benign sky"; "the benign influence of pure air")

malign (vs. benign) -- (evil or harmful in nature or influence; "prompted by malign motives"; "believed in witches and malign spirits"; "gave him a malign look"; "a malign lesion")
        => cancerous -- (like a cancer; an evil that grows and spreads; "remorse was cancerous within him"; "pornography is cancerous to the moral development of our children")

Sense 3
benign -- (kindness of disposition or manner; "the benign ruler of millions"; "benign intentions")

INDIRECT (VIA kind) -> unkind -- (lacking kindness; "a thoughtless and unkind remark"; "the unkindest cut of all")

Similarity of adj benign

3 senses of benign

Sense 1
benign (vs. malignant) -- (not dangerous to health; not recurrent or progressive (especially of a tumor))

Sense 2
benign (vs. malign), benignant -- (pleasant and beneficial in nature or influence; "a benign smile"; "the benign sky"; "the benign influence of pure air")
       => kindly -- (pleasant and agreeable; "a kindly climate"; "kindly breeze")
          Also See-> harmless#1; kind#1

Sense 3
benign -- (kindness of disposition or manner; "the benign ruler of millions"; "benign intentions")
       => kind (vs. unkind) -- (having or showing a tender and considerate and helpful nature; used especially of persons and their behavior; "kind to sick patients"; "a kind master"; "kind words showing understanding and sympathy"; "thanked her for her kind letter")