Language of Confusion: Numerous

Number showed up in the fourteenth century meaning a sum, and then a century later meaning an arithmetic figure. It comes from the Anglo French noumbre, Old French nombre, and classical Latin numerus (origin of numeral, by the way, while numerous is actually from the classical Latin numerosus). That’s from the Proto Indo European nem-, assign, allot, or take, and you know that has a bunch of unexpected descendants.
 
First of all, anything that ends in -nomy, such as astronomy. That word actually showed up way back in the thirteenth century (so yes, it’s older than number), from the Old French astrenomie, from the classical Latin astronomia, and that of course was taken from the Greek astronomia. That was taken from astronomos, where astron means star and the nomos means law or regulation. Astronomy is star law. And since nomos is from nem-,  star number isn’t entirely incorrect either.
 
How about a word that looks like number but can’t possibly be related? By that I mean numb, which showed up in the fifteenth century, meaning deprived of feeling or powerless, but also taken or seized—fun fact, the B at the end didn’t show up until the seventeenth century. It’s from the Old English niman, to seize, which, yes, is from nem-. So the take version of nem transformed into seize, which transformed into numb. Because I guess you’re “seized” if you’re without feeling.
 
But even crazier, nomad is from the same place. It showed up in the mid sixteenth century from the French nomade, which was taken from the classical Latin Nomas, which is what they called the nomads in Arabia. It’s taken from the Greek nomas, nomad, from nomos, which… yes, like astronomy. Except in this case, the nomos specifically refers to land allotted—like nem-.
 
Finally today, nemesis. Really. It showed up in the late sixteenth century from the Greek god, which is taken from the word for righteous anger, or the distribution of what is due. It’s related to nemein, distribute or allot, which is from nem-. So because the anger is distributed righteously, we have nemesis.
 
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
Tony Jebson’s page on the Origins of Old English
Old English-English Dictionary
Fordham University