Wiktionary
once and for all
adv. (context idiomatic English) finally, permanently, conclusively.
WordNet
once and for all
adv. in a conclusive way; "we settled the problem conclusively" [syn: conclusively] [ant: inconclusively]
Wikipedia
Once and for All
Once and for All is the third live album by the Japanese band Loudness. It was released in 1994 and is the only live album with the formation that recorded the album Loudness in 1992. "House of 1.000 pleasures" is a song of the band Ezo, which singer Yamada was a member of, before joining Loudness.
Usage examples of "once and for all".
If this is what it takes to prove my claim to fame once and for all, so be it.
There was still the business of the furniture to settle and when she got back, she would have to decide once and for all what she was going to do.