What is "serendipities"

n. (plural of serendipity English)

Serendipities: Language and Lunacy (originally published in English, translated by William Weaver) is a 1998 collection of essays by Umberto Eco. Dealing with the history of linguistics and Early Modern concepts of a perfect language, the material in the book overlaps with La ricerca della lingua perfetta. As Eco explains it in his preface, serendipity is the positive outcome of some ill conceived idea.