Language Of Confusion: Pulse, Redux

Time for another redo! This one’s pretty old, so it could definitely use an update. It bothers me when old things aren’t done up to my current standards. I’m sure by the time I finish updating them, I’ll have a whole new way of doing these.
 
The core word, pulse, showed up in the early fourteenth century as a noun (well, actually, there was a pulse in the thirteenth century, but it means peas, beans, and lentils and is totally unrelated to this pulse) meaning a throb, beat, or stroke. It comes from the Old French pous/pulse and classical Latin pulsus, which means drive, beat, or push. That’s from the verb pellere, to beat or to drive, which can be traced to the Proto Indo European root pel-, to thrust, strike, or drive. It actually makes sense, right?
 
Impulse showed up in the early fifteenth century, coming from the classical Latin impulsus, which means things like to push, to urge, or even to shock. It’s verb form, impellere, is really just to impel, or to push against, with the first part coming from -in, in, and the rest coming from pellere, obviously. To impel is to drive in—an inward drive. Sounds about right.
 
Repulse showed up in the early fifteenth century, as did repulsion, coming from the classical Latin repulsus (take a guess what that means) and its verb form repellere, to drive back. The re- means back, and pellere… well, obviously. It also might be obvious that this is the origin word for repel. That word showed up at the same time as repulse, although it did have the influence of the Old French repeller. To repel is to drive something back, and really, that’s what repulse means, too.
 
The rest of the words are pretty similar, although they don’t really have pulse forms. Compulsion and expulsion showed up in the early fifteenth century, though compel and expel showed up a bit earlier in the fourteenth century. Propulsion was a bit later, showing up in the early seventeenth century, and back then it meant driving away, not meaning driving forward until 1799. Propel is also a bit later than its -pel counterparts, having shown up in the mid fifteenth century, and again, meaning drive away. But then sometime in the mid seventeenth century, it started to mean drive forward, which obviously spread to propulsion. It’s actually weird when you realize pro- means forward, so propel literally means drive forward, we just weren’t using it that way for a while. As for the others, com- means with, and ex- means out, so the words are to drive with (yeah, I kind of see it) and drive out (I definitely see it).
 
Words!
 
Sources
Online Etymology Dictionary
Google Translate
Omniglot
University of Texas at Austin Linguistic Research Center
University of Texas at San Antonio’s page on Proto Indo European language