*prolusion*

n. [ L. prolusio, fr. proludere to prelude; pro before + ludere to play: cf. F. prolusion, It. prolusione. ] A trial before the principal performance; a prelude; hence, an introductory essay or exercise. “Domestic prolusions.” Thackeray. [ 1913 Webster ]

Her presence was in some measure a restraint on the worthy divine, whose prolusion lasted. Sir W. Scott. [ 1913 Webster ]