What is the definition of insidious?
1. Lying in wait; watching an opportunity to insnare or entrap; deceitful; sly; treacherous; - said of persons; as, the insidious foe. 2. Intended to entrap; characterized by treachery and deceit; as, insidious arts.The insidious whisper of the bad angel. - Hawthorne.. Lying in wait; watching an opportunity to insnare or entrap; deceitful; sly; treacherous; - said of persons; as, the insidious foe. 2. Intended to entrap; characterized by treachery and deceit; as, insidious arts. in·sid·i·ous. Treacherous; stealthy; denoting a disease that progresses gradually with inapparent symptoms. [L. insidiosus, cunning, fr. insidiae (pl.), an ambush]. /in·sid·i·ous/ (-sid´e-us) coming on stealthily; of gradual and subtle development.erily, with insidious beauty do sea and life gaze upon me round about: Thus Spake Zarathustra: A Book For All And None by Nietzsche, Friedrich View in context. They were designed for winter wear, when treacherous drafts came down chimneys and insidious currents of deadly cold found their way through key-holes. LINK / CITE ADD TO WORD LIST. adjective. The definition of insidious is something or someone who works in a subtle or sly way, or in an intent to trap. An example of insidious is a plan that is meant to scam people out of money.he definition of insidious is something or someone who works in a subtle or sly way, or in an intent to trap. An example of insidious is a plan that is meant to scam people out of money. adjective. 1  Working or spreading harmfully in a subtle or stealthy manner: insidious rumors; an insidious disease. 2  Intended to entrap; treacherous: insidious misinformation. 3  Beguiling but harmful; alluring: insidious pleasures.he definition of insidious is something or someone who works in a subtle or sly way, or in an intent to trap. An example of insidious is a plan that is meant to scam people out of money. insidious. adj. 1. stealthy, subtle, cunning, or treacherous. 2. working in a subtle or apparently innocuous way, but nevertheless deadly: an insidious illness.[C16: from Latin insidiōsus cunning, from insidiae an ambush, from insidēre to sit in; see insessorial]. (ɪnˈsɪd i əs). adj.nsidious. adj. 1. stealthy, subtle, cunning, or treacherous. 2. working in a subtle or apparently innocuous way, but nevertheless deadly: an insidious illness. [C16: from Latin insidiōsus cunning, from insidiae an ambush, from insidēre to sit in; see insessorial]. from The American Heritage® Dictionary of the English Language, 4th Edition. 1  Working or spreading harmfully in a subtle or stealthy manner: insidious rumors; an insidious disease. 2  Intended to entrap; treacherous: insidious misinformation. 3  Beguiling but harmful; alluring: insidious pleasures.rom The American Heritage® Dictionary of the English Language, 4th Edition. 1  Working or spreading harmfully in a subtle or stealthy manner: insidious rumors; an insidious disease. 2  Intended to entrap; treacherous: insidious misinformation. 3  Beguiling but harmful; alluring: insidious pleasures. insidious adjective. › (of something ​unpleasant or ​dangerous) ​gradually and secretly ​causing ​harm: High ​blood ​pressure is an insidious ​condition which has few ​symptoms. insidiously adverb uk us /-li/ › The ​disease ​begins insidiously and ​progresses relentlessly.nsidious adjective. › (of something ​unpleasant or ​dangerous) gradually and secretly causing ​harm: ​Cancer is an insidious ​disease. insidiously adverb us /ɪnˈsɪd·i·əs·li/ › His ​negative ​attitude slowly and insidiously ​spoiled the ​atmosphere around the ​office. adverb us /ɪnˈsɪd·i·əs·li/. insidious adjective. › (of something ​unpleasant or ​dangerous) gradually and secretly causing ​harm: ​Cancer is an insidious ​disease. insidiously adverb us /ɪnˈsɪd·i·əs·li/ › His ​negative ​attitude slowly and insidiously ​spoiled the ​atmosphere around the ​office.nsidious adjective. › (of something ​unpleasant or ​dangerous) gradually and secretly causing ​harm: ​Cancer is an insidious ​disease. insidiously adverb us /ɪnˈsɪd·i·əs·li/ › His ​negative ​attitude slowly and insidiously ​spoiled the ​atmosphere around the ​office. Proceeding in a gradual, subtle way, but with very harmful effects: sexual harassment is a serious and insidious problem. More example sentences. Synonyms. 1  Nuclear disc lesions are of gradual or insidious onset, the history may be on and off back pain for weeks and back pain getting worse. But for five Irish teenagers, the magnifying glass doesn't reveal the insidiousness of California-it only inflates its lure and significance. 2  Slowly, with an insidiousness no one recognized, those businesses began to disappear until now many of the buildings sit empty and abandoned. Verily, with insidious beauty do sea and life gaze upon me round about: Thus Spake Zarathustra: A Book For All And None by Nietzsche, Friedrich View in context. They were designed for winter wear, when treacherous drafts came down chimneys and insidious currents of deadly cold found their way through key-holes.erily, with insidious beauty do sea and life gaze upon me round about: Thus Spake Zarathustra: A Book For All And None by Nietzsche, Friedrich View in context. They were designed for winter wear, when treacherous drafts came down chimneys and insidious currents of deadly cold found their way through key-holes.
Working or spreading harmfully in a subtle or stealthy manner. Intended to entrap,treacherous.Beguiling but harmful, alluring.