Read Edit View history 闭子集 bìzǐjí closed subset Origin Definitions Defs Strokes Stroke Words Sentences Sents created sense approved 闭子集/閉子集 · bìzǐjí · closed subset 2026/03/04 闭子集 / 閉子集 bìzǐjí closed subset closed subset (mathematics) 这个集合是该拓扑空间的一个闭子集。 noun created sense Mar 4, 2026, 02:25 AM