capo (n.2) Look up capo at Dictionary.com
"pitch-altering device for a stringed instrument," 1946, short for capo tasto (1876), from Italian, literally "head stop," from Latin caput "head" (from PIE root *kaput- "head").
capo (n.1) Look up capo at Dictionary.com
"leader of a Mafia 'family,' " 1952, Italian, literally "head," from Latin caput "head" (from PIE root *kaput- "head").