Where does “insidiousness” come from?

insidiousness (English) comes from English insidious, from Middle French insidieux, from Latin īnsidiōsus, from Latin īnsidiae, from Latin īnsideō, from Latin īn-, from Latin în, from Latin en — in.

insidiousness (English): A surreptitious harmfulness, quality of...

Definitions

  1. A surreptitious harmfulness, quality of...

Ancestry of “insidiousness”, step by step

StepLanguageWordMeaning
1EnglishinsidiousProducing harm in a stealthy, often gradual,...
2Middle Frenchinsidieux
3Latinīnsidiōsuscunning, deceitful, insidious
4Latinīnsidiaeambush
5Latinīnsideōto sit down, in or upon; to be seated or rest in or upon
6Latinīn-un-, non-, not
7Latinînin, at, on, upon, from (space)
8Latinenlookǃ beholdǃ; reallyǃ?; come onǃ
9Proto-Italicenin
10Proto-Indo-Europeanh₁énin
Every word from Proto-Indo-European h₁énEvery word from Latin īn-Every word from Proto-Italic en