Phrase origin

Posted by Dorothy on September 06, 2001

Anybody know where this phrase originated and what it means?
"warms the cockles of my heart"

• Cockles of my heart R. Berg 09/07/01
  • Cochleae cordis? Bruce Kahl 09/07/01
    • Correction; derivation R. Berg 09/07/01
      • Cockles ESC 09/07/01