Where does “knee-jerk” come from?

knee-jerk (English) comes from English knee, from Middle English knē, from Old English cnēo, from Proto-West Germanic kneu, from Proto-Germanic knewą, from Proto-Indo-European ǵnéwo-, from Proto-Indo-European ǵónu — knee.

knee-jerk (English): Unthinking, not carefully considered, automatic,...

Definitions

  1. Unthinking, not carefully considered, automatic,...

Ancestry of “knee-jerk”, step by step

knee-jerk traces back through two separate lines of ancestry.

via English knee

StepLanguageWordMeaning
1EnglishkneeIn humans, the joint or the region of the joint...
2Middle EnglishknēThe knee or a similar joint in other animals
3Old Englishcnēogeneration
4Proto-West Germanickneuknee
5Proto-Germanicknewąknee
6Proto-Indo-Europeanǵnéwo-knee
7Proto-Indo-Europeanǵónuknee

via English jerk

StepLanguageWordMeaning
1EnglishjerkA sudden, often uncontrolled movement, especially...
2Middle Englishyerksudden motion
3Old Englishġearcactive, quick; ready, active, quick

Words derived from “knee-jerk”

Every word from Proto-Indo-European ǵónu →Every word from Proto-Indo-European ǵnéwo- →Every word from Proto-Germanic knewą →