Here's a terrific article over at BigThink.com about relationship words that don't translate easily into English. What a blast. The Yagan word Mamihlapinatapei, for example, means: "The wordless yet meaningful look shared by two people who desire to initiate something, but are both reluctant to start."
Awesome. I'm going to have to start using this word in everyday conversation. (Well... maybe every other day.) The article lists 9 more, plus a few observations about close-but-not-quite equivalents in English. It's a good time, take a look at it here.