千秋楽 (senshuraku) is also written as 千穐楽 or 千龝楽, and, being an industrial term, indicates the last day, when plays on the same program are performed repeatedly every day for two or more days.
千秋楽（せんしゅうらく）は「千穐楽」、「千龝楽」などとも表記され、複数日にわたって同じ演目を行う興行において、「最終日」を指す業界用語。