one-hit wonder
youtubeでの再生回数が話題となった、PSYは再びヒット曲を生み出すのでしょうか。
Can Psy top his 'Gangnam Style' success? History says no
Here's a look at four other artists who had it all, until they didn't.
Signature song: U Can't Touch This (1990)
Dissing the hit: With five singles that went top 10 on Billboard's Hot 100 chart, Hammer was far from a one-hit wonder. But rap purists decried his rampant sampling, saying he was stealing more than borrowing from others' songs. That there were MC Hammer dolls in toy stores and a Saturday morning cartoon, Hammerman, only added to the ridicule from his peers. He responded to the backlash by dropping the "MC" from his stage name and took a grittier stance with his music.
one-hit wonderという表現ですが、なんとなく意味は感じ取れるかもしれません。手持ちの辞書には書いていなかったのでwebで調べてみると、「1曲だけのヒットで消え去る歌手、一発屋」（英辞郎 on the WEB）とありました。Cambridge Dictionaries Onlineには、"a performer of popular music who makes one successful recording but then no others"と書かれていました。
日本では"one-joke wonder"が毎年のように登場しますね。（Astroriver）
