Kenneth G. Wilson (1923). The Columbia Guide to Standard American English. 1993.
serendipity (n.), serendipitous (adj.)
Serendipity means good luck or good fortune, unearned and unexpected. Its from Walpoles The Three Princes of Serendipthe princes had it. But these and other self-conscious polysyllables (such as thaumaturgical) should be sparingly employed. As with Turkish delight, a very little is often more than enough.