Language Of Confusion: -Solve/Solution, Redux

Solve showed up in the late fourteenth century as solven, and back then it meant to dissipate or loosen. Then in medicine, it started to mean dissolve a substance in a liquid, and then in the sixteenth century, it took on the more figurative meaning of to clear up or to answer. Finally, it meant to solve a math problem in 1737! Funny, right? Anyway, it comes from the Proto Indo European se-lu, from the word s(w)e-, which was actually a third person reflexive pronoun. And is also the origin of idiom. Basically, idiom came from the Greek idios, which came from the PIE swed-yo, which, drop the S, and yeah, that tracks.
 
Then there’s solvent, which is actually fairly recent, having shown up in the mid seventeenth century meaning to pay what you owe, and then a little later something that can dissolve something. Plus there’s solution, which showed up in the late fourteenth century meaning both the dissolving of something and an explanation. It’s from the Old French solucion and the classical Latin solutionem (bet you can’t guess what that means). That’s from the verb solvere, to solve or to dissolve, and that’s from se-lu.
 
Next, let’s look at some prefixed versions. Resolve showed up in the late fourteenth century, also meaning to melt or dissolve, and pretty much the same is true for resolution. How did it get to mean what we use it as? Well, first it meant to separate into components, and then to mentally separate into components, which led to resolve. Both words come from the classical Latin resolvere, to analyze or to loosen, with the re- prefix meaning back. To resolve is to solve back, which makes sense when you know that one of resolve’s meanings in the fifteenth century was to condense into a vapor. Basically, resolve meant dissolving something backwards.
 
Speaking of dissolve, it showed up in the late fourteenth century meaning to break up, meaning this one actually kept its definition. It’s from the classical Latin dissolvere, to dissolve, with dis- meaning apart here. To dissolve is to break apart. And the only one of the solve words to stick to its original meaning through the centuries.
 
Finally today, absolve showed up in the early fifteenth century meaning release, from the classical Latin absolvere, to acquit or set free. The ab- means off or away from, and with solvere meaning to loosen, absolving is loosening off, which sounds kind of nonsensical but does go with setting free. Absolute showed up in the late fourteenth century, meaning free from limitation, and from the Latin absolutus, a past participle of absolve. When you’re totally free, you’re absolute!
 
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