There are quite a few two-kanji compounds that share a radical; often on the left side. This radical also seems to be closely related to the meaning. Most of the time the kanji are not jouyou, though, but often the kanji are not used anywhere else. I’m wondering if there is a special kind of term for these words? Does anyone know why/how they came to be?
Some examples off the top of my head that are common enough to recognize (but don’t ask me to write them 
) include 蹂躙、邂逅、躊躇、徘徊、彷徨.
Ooo, ooo, 挨拶.
Well, that’s kinda the how/why they came to be, isn’t it? Jukugo often use two kanji with similar meanings to reinforce them.
蹂 = step on, 躙 = step on, 蹂躙 = very step on. All with feet.
徘 = wander, 徊 = wander, 徘徊 = very wander. All with… loitering man?
Yeah, I guess it just somehow feels like a special case, since the kanji are not really used anywhere else. But I hadn’t really thought of the individual meanings, since you don’t really know them from beforehand. Maybe there’s nothing more to them…
珈琲? But I don’t know the individual meanings.
Edit: that’s right, ornamental hairpins + string of many pearls = bitter roasted berry drink
I’m aware this is ateji, but it fits your first rule, at least
珈琲 is, after all, the drink of kings.
芭蕉, the pen-name name of 松尾芭蕉, the haiku writer.
It means “banana”. So do the individual kanji.
I don’t know if there’s a term for it but I’d like to mention the existence of 存在, I find it cute for some reason.
喧嘩 is one of my favorites
I just mentioned 瀟洒 in another thread! Now I’m trying to figure out what 氵 has to do with being stylish.
I was reminded when posting in another thread that 味噌 also shares radicals.
Mmm, miso. Very mouth.
The 存在 of 存在?
雌雄 (しゆう) female and male animals
牝牡 (ひんぼ) female and male animals
I suppose 塊魂 doesn’t count as jukugo but even before I started learning Japanese it was interesting to me to see that the two symbols are almost the same.
It’s a jukugo (an invented one, sure) but the dictionary radicals are the part that’s different. For 塊 it’s 土 and for 魂 it’s 鬼, so not quite the same category of word, but a compound I think people do like.
Arguably, all jukugo are invented. 
Oh. Not 云?
some more WaniKani vocab: 犠牲, 跳躍
Or, are they discovered?
(jazz hands)
Just saw 捻挫 in an anime and thought of this topic !
Also 曖昧, 葡萄, 麒麟
And of course the mighty 魑魅魍魎
How about this one: 魂魄（こんぱく）? Have you heard of it? It’s 100% ‘real’, and it’s used in Chinese too! 
(PS: I’m not so sure about what the dictionary radicals are, but I think they fit the visual pattern we’re looking at anyhow.)
Found an animal:
蝙蝠
Even though a bat is not an insect…