The foxtrot was a dance. The Sixth Doctor once learned it from a woman named Rebecca after he had quickly mastered the waltz. (PROSE: Teach Yourself Ballroom Dancing)
In 1941, Jack Harkness fought with George briefly before the real Jack Harkness pulled them apart. He told George to apologise, adding, "I think it was your fist in his face he didn't like, not your foxtrot." (TV: Captain Jack Harkness)