rocks (n.)youdaoicibaDictYouDict[rocks 词源字典]
plural of rock (n.1). Meaning "ice cubes" is from 1946; slang meaning "testicles" is first recorded in phrase get (one's) rocks off "achieve intense satisfaction." On the rocks "ruined" is from 1889, figurative use of the expression with reference to ships (by 1735).[rocks etymology, rocks origin, 英语词源]