Stories We Like: A Guide to the Comma
late 14c., "restatement, repetition of the words of another," from rehearse + -al (2), or from Old French rehearsal "a repeating." Sense in theater and music, "act of rehearsing," is from 1570s. Pre-wedding rehearsal dinner attested by 1953.
rehearsal re·hears·al (rĭ-hûr'səl)n. The process of repeating information, such as a name or a list of words, in order to remember it.