What does it mean?

serendipity (n)

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ser·en·dip·i·ty

 [ sèrrən díppətee ]   

1. discovery of something fortunate: the accidental discovery of something pleasant, valuable, or useful
2. gift for discovery: a natural gift for making pleasant, valuable, or useful discoveries by accident

Synonyms: fate, destiny, karma, providence, luck, fortune, coincidence, accident, kismet,chance