Playing Death Stranding (the first, never finished my playthrough back when it came out) and reading all the notes really has my lookup history looking interesting right now.
臍帯 (さいたい, umbilical cord)
線虫 (せんちゅう, nematode)
イベリコ豚 (イベリコぶた, black Iberian pig)
中性子線 (ちゅうせいしせん, neutron beam)
I think I’d have been more concerned if I didn’t have to look those up 
To be fair I do loosely know 中性子 without the beam bit from reading lots of sci fi jargon in some visual novels, though it’s kinda vague because, I mean, so are neutrons for me in English. 臍帯 I was good with in context but just don’t recall coming across the 音読み for 臍 . But yeah no experience at all with nematodes or specific types of pig haha.
The piggy was the only one I figured out from your list, being aware of the breed… they make for yummy jamón ibérico 
Nematode I even had to look up in English 
Looked up if I had encountered it before, and I had, in this set expression:
臍を曲げる - to get angry / to become perverse (it was used with the first meaning in my case)
Perverse can mean to be in a bad mood, so I’m pretty sure it’s just the same meaning worded two ways.
Oh thanks, today I learned 
Two for today, very different types. First off, 多能性幹細胞 (たのうせいかんさいぼう). It’s a form of stem cells. Did not enjoy being hit with that in a game cutscene.
After, Hundred Line gave me, all in the same sentence: 激おこぷんぷん丸, マジまんじ, and カム着火インフェルノ.
The first and last are apparently part of a whole anger slang hierarchy of steps: 激おこぷんぷん丸 - Wikipedia
激おこぷんぷん丸 is the most popular and also it’s really fun sounding.
I actually learnt an English word today. Limpid. It’s completely clear (like clear water). I’d heard the word before, but I never thought about what it meant before.
引け目 ひけめ one’s weak point
when i was reading i was like “what are we pulling???” until i finally decided to look it up and damn now the whole paragraph makes much more sense 
厠 (かわや) - dated word for a toilet. You really need to know all kinds of things to read. Looks like it’s this sort of hole in the ground:
My impression is that it can be any kind of toilet, though obviously as an out of date word it’s more likely the author had an out of date toilet in mind. Tanizaki has a good essay 厠のいろいろ, which I think is where I first ran into this word, and he mentions a variety of them…
Ahh that makes sense, good to know, thanks!
Picked this up from an Instagram reels today in the toilet:
「ちゃちゃ入れねぇ」
Means 「Don’t interfere」
Explanation:
「ちゃちゃ」「茶々」: Means tea and the thing alike.
「入れる」: Means to put in.
The story is, if someone is doing something, and you bring the tea into their work (to chat, to take a break, etc.) it means that you’re interfering them.
This was quite the pain to look up
ゲリラ豪雨, gerira gō’u
A guerrilla rainstorm (ゲリラ豪雨, gerira gō’u) is a Japanese expression used to describe a short, localized downpour of over 100 mm per hour of rain caused by the unpredictable formation of a cumulonimbus cloud. The term is often used by the Japanese media in reporting such events, but does not have an official meaning nor is it used by the Japan Meteorological Agency.
I keep seeing this pop up a lot recently (a look at the weather forecast right now tells me why) but haven’t bothered looking into the actual reason it’s called that, it seems like a weird one.
The JP wikipedia page says it became a commonly used phrase in weather reports etc sometime around 2008, even though it had been used a while before that more sparingly
不朽ー ふきゅう immortal/undying
I recently saw this at the guitar store on a cashier’s tattoo. When I asked him about it he said it was from Iraq. He had been shot at twice and survived them both, but wasn’t feeling all that invulnerable due to his age. I recognized the first kanji but not the second.
