facetiosityrare.|fəˌsiːʃɪˈɒsɪtɪ| [f. next; see -ity.] The quality of being facetious; in quot. quasi-concr. 1822Liberal I. 209 The bookseller..evidently..laughs at the customer..when he has the luck to get rid of some heavy facetiosity by a chance sale.