Wiktionary
adv. (context idiomatic colloquial English) thoroughly, completely, in every way imaginable
Wikipedia
Six Ways to Sunday is a 1997 crime drama with elements of comedy directed by Adam Bernstein. It is based on Charles Perry's novel Portrait of a Young Man Drowning.
Usage examples of "six ways to sunday".
But the moment I try to leave the country, or even the city, I'm going to be searched six ways to Sunday, and since I am not known as a religious man, sooner or later one of the gendarmes is going to send some telegrams to various religious organizations or antiquarian bookdealers, and then the shit will hit the fan.
The state cop says you're a pain in the ass and will bend the law six ways to Sunday.
Now, if we was to become partners and you really do take over the world, you could give me a little chunk of it, like say, Australia, and we could plunder it six ways to Sunday and split the take right down the middle.
He drove us six ways to Sunday and back again, and did more than I would have thought possible with that thing he's riding.
Dynamite won't kill it, but it would screw our magical wards six ways to Sunday.
Didnt he know by now that I was screwed six ways to Sunday, and he shouldnt depend on me?