Meaning and Usage of 某 (bou): it is a very unique Japanese term that is used in writing to refer to a thing or person anonymously, sometimes in a sarcastic way.
Meaning and Usage of コスパ (kosupa): it is short for コストパフォーマンス ("cost performance"), but it contains much wider senses in Japanese.
Meaning of 鬼 (oni) in Japanese and 鬼-related slang/Idioms, including 鬼のように (oni no youni), 鬼の目にも涙 (oni no menimo namida), 鬼かわいい (oni kawaii).
Meaning and Usage of へったくれ も ない (hettakure mo nai): "X も へったくれ も ない" (X is an arbitrary noun) is an idiomatic Japanese expression that means “there is no X or anything (at all)”.
This post explains four meanings of ノリ (nori) (e.g. ノリでやった) and 悪ノリ (waru nori) in Japanese with plenty example sentences!
Meaning and Usage of 腹八分目 (hara hachi bun me) and 分 (bun) in Japanese. 腹八分目 literally means “belly/stomach 80%” and indicates the act of eating food until you feel 八分 (80%) full, not 十分 (full/100%).
Meanign and Usage of 騙されたと思って (damasareta to omotte): it is a casual Japanese expression that literally means "(Please) pretend that you've got duped (by me)" and figuratively "Just do it, trust me!" or "Take my word!".
Definition and Examples of 職業病 (shokugyou byou): it literally means "occupational disease", where 職業 (shokugyou) means "a job/occupation" and 病 (byou) means "disease". However, in a casual context, it also refers to your habits that you cannot cannot help doing because you always do them a lot at work.
The Japanese idiom "(自分のことを) 棚に上げる (tana ni ageru)" literally means "put (oneself) up on a shelf" and figuratively means "to behave hypocritically", just like "the pot calling the kettle black".
Meaning and Usage of 回し者 (mawashi mono): it originally means "a spy", but nowadays it's more often used to indicate a person who advertises something (often in a stealthy way).
Meaning of なんでやねん (nandeyanen) and detailed examples of how to use nandeyanen in a Japanese conversation: An essential phrases in Osaka
Definition and Usage of 元を取る (moto wo toru): it means "get your money's worth", i.e. "get what is worth the money you have paid".
This post gives you an example of casual speech in Japanese, with a special focus put on Japanese abbreviated words, such as ググる (guguru)