Language Of Confusion: Acting!, Part III

Back to the continuing series of words descended from the Proto Indo European root ag-, to drive, draw out, or move. This week… well, they all have A in them, but it’s going to get weird.
 
First, ambassador. Yes, really. It showed up in the late fourteenth century from the Old French embassator/ambassateor, from the classical Latin ambactus, a vassal. In a shocking twist, that word’s actually from the Celtic ambiactos, a messenger or servant, which is from the Proto Indo European ambhi-, around, and ag-. An ambassador is to move around. I guess the amba- is the around part, so does that mean the ass- is actually from ag-???
 
Similarly, there’s embassy. It showed up in the late sixteenth century actually meaning the position of an ambassador (remember, they also used to spell that with an E), not meaning the place of an ambassador until the mid eighteenth century. It has pretty much the same origin, just from the French embassee, and ultimately the PIE ambi-ag-to, which like with ambassador, is ambhi- + ag-. So yeah, the ass- is the ag-.
 
Speaking of ass—I mean, kind of—there’s assay, which showed up in the fourteenth century as a verb that meant to try and then a noun that meant test of quality. The words come from the Anglo French assai and Late Latin exagium, a weighing. No, I don’t get it. Maybe it will make more sense when we look at its cousin, essay. Yes, that essay. It showed up in the sixteenth century as a noun meaning trial or attempt, and a century earlier as a verb meaning to test. It’s from the French word essai, which means an essay or a test, and it’s also from exagium. That’s from the classical Latin verb exigere, to demand, test, or drive out, with the ex- meaning out [https://www.etymonline.com/word/ex-] and the rest from agere, which we talked about last week and the week before as meaning to act. An essay is… to act out. Why did it come to mean writing? Because much like assaying involves unpolished materials, an essay is supposed to be unpolished writing. Which means all those revisions to essays they made me do in high school were incorrect for the format!
 
Can we make it any weirder? I think so. Axiom showed up in the late fifteenth century, from the French axiome, and classical Latin axioma. That was actually taken from the Greek axioma, which could mean an office, authority, or just an axiom. That’s from axios, worthy, from the Proto Indo European ag-ty-o-, weighty, and that ag- of course is to drive. So it went from weighty, to worthy, to authority, to an axiom. Sure.
 
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
Fordham University
Orbis Latinus