forgotten arm
n.— «While boxing informs “The Forgotten Arm”—the title refers to an obscure term for a surprise punch—she’s not about to draw comparisons between music and boxing, unscrupulous management practices inherent to both aside.» —“Aimee Mann to take stage at festival” by Regis Behe Pittsburgh Tribune-Review (Pa.) June 16, 2005. (source: Double-Tongued Dictionary)