Word of the Day: INSIDIOUSPronunciation: UK /ɪnˈsɪd.i.əs/ US /ɪnˈsɪd.i.əs/Meaning'Insidious' describes something that is harmful but develops gradually and subtly, often without being noticed at first. Origin and historyThe word insidious entered the English language in the 16th century. Also Read: Word of the Day, August 8Cultural significance and modern usageToday, "insidious" is often used to describe dangers that are difficult to recognise because they do not appear threatening at first. "The insidious influence of the Jesuits." — The War of the Worlds by H. G. WellsSynonymsCunningDeceitfulSubtleStealthyTreacherousSlyDeviousPerniciousAntonymsObviousHarmlessOpenInnocentBenignTransparentForthrightRead more Word of the Day here