ROTATING CROWD

Turbulent has had quite the turbulent etymology! It was borrowed into English in the early fourteen hundreds, and referred more to people being disorderly than anything more abstract. It had the same spelling and definition in Middle French, but as Latin turbulentus it could mean anything from "stormy" to "confused"- describing a state of unrest in general. Here we can eliminate the suffix -ulentus, meaning "full of", which leaves us with the root turba, which could mean "turbulent" or "crowd". Although it's uncertain, turba could be from the Ancient Greek word turbe, still meaning "turmoil". This would be reconstructed as deriving from the Proto-Indo-European root stwer, meaning "to rotate" because something rotating is in turmoil). Usage of both the words turbulent and turbulence has been decreasing since a peak around the year 1800- I suppose even that is turbulent.