Honestly, at this point, I’d be disappointed if you don’t remember that the word case (like a container) comes from the Proto Indo European kap-, to hold/grasp,. It’s led to some… weird descendants.
I suppose it’s not totally crazy that heavy comes from kap-, since after all, you determine something is heavy by holding it. It comes to us from the Old English hefig, heavy, and that g is actually representative of a y sound, so pronunciation-wise it wasn’t all that different. It comes from the Proto Germanic hafiga, having weight, and that’s from kap-. I guess we can judge this one as a reasonable origin.
Heave being related also kind of makes sense. It’s from the Old English hebban, lift or heave, from the Proto Germanic hafjan, and that is also from kap-. Heft is from the same place; it just has a past tense in the same sense of thieve/theft.
How about we get into something weirder? Like hawk. As in the bird. It showed up in the fourteenth century as hauk (even earlier as havek), from the Old English heafoc, which is just hawk. It’s from the Proto Germanic habukaz, which is from kap-, although there’s no real explanation as to why a bird is named for grasping. I guess they’re really good at grabbing stuff. Oh, and hawk, like hawking goods is not related at all. Totally different origin. Words!
Now for the last word we’re looking at… purchase. Yep. It showed up in the fourteenth century from the Anglo French purchaser, which is from the Old French porchaicier. That word has the prefix pur- (might be intensive here, or meaning forth), and the chacier means chase. Which we looked at last week and basically means to hunt, and hunting results in taking hold of something—or grasping it. You chase after a purchase, I suppose.
That’s it. We’re finally done! And… now I have to start coming up with new subjects again.
Tony Jebson’s page on the Origins of Old English