This is dedicated to those words/kanji that you may not encounter all the time so you kind of forget it, but when you see it again you think, “oh right!”. Or for when you learn a new vocab word that just makes a ton of sense to you and you think, “aha!”.
Mine “oh right” word is 爆発 (ばくはつ) which means explosion. I dont talk about explosions often so whenever I see it, this word crawls out from the depths of my brain haha
What are your words?
Not quite the same but figured I’d share anyways. I recently learned the word 真夜中 and actually went “this actually makes sense” compared to many kanji combinations. I always love when that happens.
That happened with me and ハリネズミ、like yes, a needle mouse is absolutely a hedgehog. Honestly I think it makes more sense than the english name haha
I just learned the 今日は vocab. I’ve always only seen that as written out Hiragana, so I did not see that coming. But I had heard that the は at the end used to be a legitimate topic marker, so that the phrase was literally something along the lines of “talking about today,” so the kanji make total sense.
Haha this reminds me of this video (the whole thing is great but the part Im talking about is at 2:06)
Not sure about anyone else, but I used to love Fushigi Yūgi as a kid, so when I recently learned 不思議, it just clicked so well for me. 
I just learned the Kanji for Joke 冗談, a word i’ve known for a long time and I never expected those kanji. but it makes sense… superfluous dialogue…
For me I learned the word 不思議 from Bulbasaur. The Japanese name for Bulbasaur is フシギダネ, I especially like it because it can also be interpreted as 不思議だね which means “mysterious, isn’t it?”.
what on earth; japanese pokemon names are wild.
visiting my parents earlier this year, i found some old jp pokemon cards, and learned that articuno/zapdos/moltres are サンダー・フリーザー・ファイヤー, which are, hm… less creative than the english version’s own foreign language joke.
The pun goes yet deeper, as 種 (たね) is “seed.”
Mystery seed/“It’s a mystery, huh.”
And yes, that’s the same 種 that WK gives you for 種類 and 人種 early on, without alerting you as to the kunyomi or stand-alone vocab meaning. But doesn’t it make sense that meanings including “seed,” “material,” “category” and “cause” can all be linked to one kanji?
漢字はやっぱり不思議だね
(I personally remember 不思議 thanks to our buddy Bulbasaur and the first Dragon Ball theme song. Also the reason I remember (大)冒険.)
Mine is 世界, but not when reading it, when hearing it, I’ll be watching something and not read a sub, or listening to some music and always go aha, the world!
That is actually one of my favorite Japanese pokemon names!! =D
It’s just so… silly! =D
Just call it out in a dramatic voice! 
The Eeveelutions have some fun ones too: イーブイ Eievui (eevee) is possibly just short for Evolution.
シャワーズ Showers (vaporeon), サンダース Thunders (jolteon), ブースター Booster (flareon), エーフィ Eifie (espeon), ブラッキー Blacky (umbreon), リーフィア Leafia (leafeon), グレイシア Glacia (glaceon), ニンフィア Nymphia (Sylveon)
That was so fun! i will have to check out his account! =D
I like 手首 and 足首 (wrist and ankle respectively).
It’s so strange describing wrist/ankle as the hand/foot’s neck. Yet it makes so much sense to me!
Okay, here’s one I just learned: 一罰百戒, meaning “punishing a crime to make an example for others”.
Another one of my favorites is 一夫多妻, meaning “polygamy”.