insidious · adj — causing harm in a stealthy, often gradual, manner. It carries an Arena rating of 1935, earned across 6 head-to-head judged battles.
Definition from Wiktionary (CC BY-SA 3.0).
Among words judged in Lexicurio's Arena, insidious ranks #210 of 17,143 for Scariest Words, #356 of 17,134 for Words That Escaped Their Books, #663 of 17,144 for Most Malleable Words, #709 of 17,150 for Most Incisive Words.
insidious is pronounced /ɪnˈsɪdi.əs/.
Why “insidious” is a great word
Working by gradual, subtle, yet ultimately harmful encroachment. From the Latin insidiae ("an ambush, plot"), from insidere ("to sit in or on"), from in ("in") + sedere ("to sit"), first recorded in English between 1535 and 1545. Unlike "pernicious" (which stresses overt destructiveness) or "invidious" (which stirs envy), "insidious" is treachery in slow motion. It is the hairline crack widening imperceptibly in a foundation, the symptomless toxin accumulating in soft tissue, the warm smile concealing a debt soon to be called in—a quiet betrayal that waits, seated within the walls, until the structure finally sighs and gives way.
❧ Essay by Lexicurio’s AI · definition, etymology & citations from published sources
Etymology
From Middle French insidieux, from Latin īnsidiōsus (“cunning, artful, deceitful”), from īnsidiae (“a lying in wait, an ambush, artifice, stratagem”) + -ōsus, from īnsideō (“to sit in or on”), from in (“in, on”) + sedeō (“to sit”).
adj
- Causing harm in a stealthy, often gradual, manner.e.g.“Strong and vigorous man as he looks, Livingstone has been for years the victim of a secret and insidious disease.” — 1847, George Lippard, The Quaker City: or, The monks of Monk-Hall:
- Intending to entrap; alluring but harmful.e.g.“Hansel and Gretel were lured by the witch’s insidious gingerbread house.”
- Treacherous.e.g.“The battle was lost due to the actions of insidious defectors.”
Definitions & examples from Wiktionary (CC BY-SA 3.0).
Words closest in meaning
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