insidiousyoudaoicibaDictYouDict[insidious 词源字典]
insidious: see session
[insidious etymology, insidious origin, 英语词源]
insidious (adj.)youdaoicibaDictYouDict
1540s, from Middle French insidieux (15c.) or directly from Latin insidiosus "deceitful, cunning, artful," from insidiae (plural) "plot, snare, ambush," from insidere "sit on, occupy," from in- "in" (see in- (2)) + sedere "to sit" (see sedentary). Related: Insidiously; insidiousness.