While watching a variety program on NTV over lunch a few weeks ago, I happened to see the word 儚い (hakanai) flash up on the screen.
I didn't recognize it right off — I can only speculate how many viewers did, as it is a 表外漢字 (hyōgai kanji), i.e., it does not appear in the list of 2,136 常用漢字 (jōyō kanji, regular-use Chinese characters stipulated by the Ministry of Education). Fortunately the character was accompanied by explanatory furigana, the little superscripts, which are positioned at its upper right, usually but not always in hiragana.
Hakanai can mean fleeting, transient, short-lived, momentary, ephemeral, fickle, vain and so on. It's a Japanese word I seldom see, let alone use. That said, the kanji (儚) is not particularly difficult; it's broken down into 亻 (ninben, the person classifier), to the right of which appears 夢 (yume, dream). Yes, here's a good case where the components in a character seem to make perfect sense: people's dreams are fleeting.