Singing Soprano Meaning

(idiomatic, euphemistic, of a man) Castrated or injured in the testicles.

Example: 2007 July 18, David Greisman, "Fighting Words—When Losers Win and Winners Lose," boxingscene.com (retrieved 26 Aug. 2008):
  Judah threw brilliant counters that temporarily stunned the undefeated welterweight titlist, endured two flagrant but apparently unintentional low punches that would've left many permanently singing soprano.