A very popular slang that we hear in Japan is YABAI [やばい]. This word can mean something good or bad depending on its use and context, which causes great confusion and curiosity among Japanese language students. In this article, we will understand a bit of the meaning of this word and see some example sentences.
First of all, the word YABAI [やばい] means something dangerous, inconvenient, risky, and terrible, that is, an adjective that shows that something bad is happening. The problem is that this same word is slang used to indicate something great, surprising, and cool. But how can a word also mean the opposite of itself?

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Is Yabai a good thing or a bad thing?
It's hard to understand how the word YABAI [やばい] came to mean the opposite. Throughout the history of various languages, young people end up inventing slang that takes on meanings or is used at unrelated times.
Every language has words and slang that are far removed from their original meaning. Often these words are used to talk about something nice or bad. Can you think of any in your language?
Likewise YABAI [やばい] is used in a way that cannot express a logical meaning, and can be used on different occasions to show that you are impressed or surprised.
The word やばい can be understood by context, just like most Japanese words that if heard in isolation can cause confusion. It makes as much sense as calling friends you love stupid and dumb and calling strangers bro.
We recommend reading: Slang in Japanese - Guide to the most commonly used in Japan

The slang YABAI used by young people
Before we understand more about the meaning of this word, we should understand where it fits in. Yabai is a slang word known as WAKAMONOKOTOBA [若者言葉] which literally means words of youth.
These are slang used mainly by teenagers around the age of 20, which are rarely used in other generations or have a totally different meaning. やばい has been used by young people with different meanings since the 2000s.
Its original meaning is something dangerous and unexpected, but over time people began to use it to make positive evaluations. In short, yabai means not good, but over time it began to mean "I was surprised and shocked unexpectedly".

History and origin of the Word Yabai
It's not known for sure how this word came to be used, but its origin probably comes from the Edo period, when the jargon YABA was used by thieves to refer to guards. So whenever they saw a guard (a dangerous situation) this word was used.
Others also say that Yaba in the Kanto dialect refers to the firing range used by Matoya during the Edo period. The word also referred to a place of prostitution, becoming a secret word for a dangerous place and a dangerous situation.
Others claim that the slang comes from the word "ayabui", which means "dangerous". Others say it comes from the expression "ya abunai", which also means dangerous. Even though its origin is uncertain, its initial meaning has always been something bad.
Already in the 80's young people used this word constantly to say that something was not cool, but only in the 90's young people started to invert its meaning to something good, cute, delicious, cool and amazing.
It's not related, but YABAI [野梅] can also refer to a wild Japanese plum or apricot.

Different ways to use Yabai
You've just eaten something tasty and you can say: "Kore Yabai!", so you're saying that it's tasty. Be careful with the tone of voice, manner and occasion when saying kore yabai, because it can also mean "that's terrible".
You can use the expression "Kare, Majide Yabai!" to say that a man is handsome. The word majide means serious which can give the meaning of really and so. In other words, he's so handsome. that both men and women can use this expression, but beware that it can sound a bit rude.
Others, when they're late for something, often say to themselves the expression yabai yabai... Worried about rushing to get to the agreed place. It was as if he was saying to himself "I need to hurry".

Yabee, Yabei, Yabasu e Majiyabasu
It is worth ing that the word has different variations such as:
- Yabee [やべー]
- Yabee [やばっ]
- Yabee [ヤベえ]
- Yabei [やべい]
- Yabasu [やばす]
- Majiyabasu [まじやばす]
The use of these slang varies by region, phrase, and occasion.
Examples of use of Yabai
Some young people use this word as “very” so it can indicate that something is very good or bad. See the example below:
一個千円のクッキーなんてやばい高いよね?
Ikko sen'en no kukkī nante yabai takai yo ne?
A 1000 yen cookie is pretty expensive, don't you think?
Below are some more sentences:
明日のテストやばそうだ.
Ashita no tesuto yaba-sōda.
I'll probably fail the test tomorrow.
やばい!課題を提出し忘れた!
Yabai! Kadai o teishutsu shi wasureta!
Crap! I forgot to do my homework.
警察はやばい仕事です。
Keisatsu wa yabai shigotodesu.
Being a police officer is dangerous.
やばい! 雨降ってきた!
Yabai! Ame futtekita!”
Shit! Started to rain!"
Yabai Desu Ne Meme
Pecorine or Eustiana von Astraea is a character from the Anime and Game Princess Connect Re: Dive. She is the master of the guild 'Gourmet Building'. This character became a meme because of her sentence endings saying yabai desu ne.
This is something similar to the dattebayo that Naruto talks about. In the official English subtitles they translated it to "How Crazy is that?" something like "How Crazy is that?". Of course, this translation doesn't make much sense in my opinion, she just wants to emphasize her sentences.