n. An unsought, unintended, and/or unexpected discovery and/or learning experience that happens by accident and sagacity.
n. A combination of events which are not individually beneficial, but occurring together produce a good or wonderful outcome.
The Century Dictionary and Cyclopedia
n. The happy faculty, or luck, of finding, by “accidental sagacity,” interesting items of information or unexpected proofs of one's theories; discovery of things unsought: a factitious word humorously invented by Horace Walpole.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. good luck in making unexpected and fortunate discoveries
Word Usage
"The word serendipity comes from the Persian fairy tale"