I've never heard it anywhere as a USian. It seems the type of obscure and redundant word that people bring out once per decade. Without looking it up, I could g

I've never heard it anywhere as a USian. It seems the type of obscure and redundant word that people bring out once per decade. Without looking it up, I could guess horn refers to phone and swoggled is another swindled, so to hornswoggle is to phone-scam.