окончательно

1) General subject: book and the candle, by bell book and candle, completely, conclusively, decidedly, decisively, definitively, determinately, for good, for keeps, roundly, that's flat, ultimately, with bell, finally, once and for all

2) Colloquial: by bell, book and candle

3) American: plumb

4) Mathematics: definitely

5) Psychology: eventually

6) Jargon: all the way

7) Makarov: down to the ground, for good and all

8) Phraseological unit: come down to