A shindig presumably references digging one's shins in e.g. folk digging in their shins for a rousing barn hoedown*, with moonshine and buxom cousins in ample supply.
Other "ahhh" words you may have taken for granted:
Passport -- you pass the port on your way out of the country.
Skyscraper -- the buildings scrape the sky, you see.
*Remember Whose Line Is It Anyway? hoedowns? Could never get into the US version. Wonder what Clive Anderson is up to these days (if he's still alive) ?