Un-translate-able words

I wish there were a word for this concept: words from other languages that have no counterpart in one's native language. Even describing this is a mouthful! Any suggestions for coining a word for that? Maybe... "counterpart-less foreign words"??

In my curiosity about the Japanese language, I have had many questions so far. And, instead of productively answering them, I have idly stumbled upon several lists of these counterpart-less foreign words. There are some commonly-known ones from French and German, of course (Schadenfreude, l'esprit de l'escalier), but here are some from Japanese that I liked:

koi no yokan:

The sense one can have upon first meeting a person that the two of you are going to fall in love. Differs from “love at first sight” as it does not imply that the feeling of love exists, only the knowledge that a future love is inevitable.

ikigai:

Ikigai is a Japanese word meaning “reason for being.” On the island of Okinawa, it is thought of as “a reason to get up in the morning,” a philosophy which has been linked to the longevity of the people there.

yuugen:

Yugen is at the core of the appreciation of beauty and art in Japan. It values the power to evoke, rather that the ability to state directly. The principle of Yugen shows that real beauty exists when, through its suggestiveness, only a few words, or few brush strokes, can suggest what has not been said or shown, and hence awaken many inner thoughts and feelings. (also on Wikipedia)