Another item from Peter Grad (whose articles for some reason are largely unavailable online):
Linguist Christopher Moore scans the globe in search of words that are not easily translatable into English. In the Republic of Congo, for instance, he found ilunga, which 1,000 translators deemed the world's most untranslatable word: As best as they can describe it, it means "a person who is ready to forgive any transgression a first time and then to tolerate it for a second time, but never for a third time."Ah, language!
There is also the Czech litost (pronounced lee-tosht), meaning "a state of torment created by the sudden sight of one's own misery."
And the beautiful French idiom esprit de l'escalier, which refers to the clever reply one thinks of only afterward, in this case, on the way down the stairs after having made a remark in an upstairs room.
Grad's article was inspired by a story on National Public Radio, which you can read about and listen to here.