Denshi Jisho — Online Japanese dictionary

ずっと 1: continuously in some state (for a long time, distance); throughout; all along; the whole time; all the way;
2: much (better, etc.); by far; far and away;
3: far away; long ago;
4: direct; straight
Common word, Adverb 
ずっと前に ずっとまえに a long time ago
Expression 

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