Wabi sabi
Karin Fong collects interesting words from other languages that don't have an equivalent in English. She says that these words "show us where the holes are in our thought patterns." When she finds a word, she makes a flash card for it.
She's recently suggested five words that we should borrow to fill some gaps in the English language.
My favorite is wabi sabi, which I first learned from Scott Berkun.
Karin gives a much better description of wabi sabi than I could:
[T]he Japanese word wabi sabi, means a beauty that comes from irregularity (wabi) and age (sabi) . A favorite pair of worn jeans, the cracked glazed texture of pottery, the patina of a metal wall, all of these illustrate wabi sabi. It's not about mass produced, pretty and smooth. I like my sleek iPhone as much as the next person, but there is value in recognizing the beauty that improves with time. It can influence how much and how fast we consume, and bring our attention to more crafted, unique things.
It's a perfect word that highlights a concept the English language lacks. It reminds me of my favorite moment in Objectified, when Bill Moggridge spoke about products "wearing in," as opposed to "wearing out."
The other four words are just as perfect and illuminating, but you'll need to read Karin's article to find out what they are.