What's an "icky thump"? was the most-asked question upon the earliest airing of the title and lead-off track of from the duo's sixth album. "It's actually 'ecky thump,'" explained Jack White to Rolling Stone, "a Northern English phrase meaning, 'What the heck?'" that he learned from his British-born then-wife, Karen Elson. As a song, it's atypical for the Stripes: Not only does it have a synthesizer, but it also has political heft, confronting America's contentious immigration policies. The Grammy-winning performance also served as a swan song: It was the last time a single by Jack and Meg White as the White Stripes topped the charts.