Trending: insidious

Lookups spiked 1,800% on November 5, 2019

Why are people looking up insidious?

Insidious was among our top lookups on November 5th, 2019, the first time the word has been in such a position since 2014, when it spiked during coverage of the Ebola virus. The recent spike in interest in insidious came from Ambassador Sondland using the word to refer to President Trump’s reputed attempts to coerce Ukraine into investigating one of his political rivals.

What does insidious mean?

Insidious came into English in the early 16th century, initially with the meaning of “awaiting a chance to entrap, treacherous.” The word may be traced to the Latin insidiae, meaning “ambush.” Additional meanings of insidious include “having a gradual and cumulative effect” and “developing so gradually as to be well established before becoming apparent” (said of a disease).


As doth Tullie in the oracion that he made for one Aulus Cecinna wherin he begynneth his proeme thus If temerite and lake of shame coulde as moche preuayle in plees afore the iustices as doth audacite and temerarious boldenesse in the feldes and deserte places there were no remedie but euen so muste Aulus Cecinna be ouercome in this matter by Sextus Ebucius impudence as he was in the felde ouercome by his insidious audacite.
— Leonard Cox, The art or crafte of rhetoricke, 1532

Trend Watch is a data-driven report on words people are looking up at much higher search rates than normal. While most trends can be traced back to the news or popular culture, our focus is on the lookup data rather than the events themselves.

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