Leviticus 15:25

‎ימים רבים [AND IF A WOMAN HAVE AN ISSUE OF HER BLOOD] MANY DAYS — at least three days (since the plural ימים suggests at least two days, the word רבים, “more", must imply at least three days) (cf. Sifra, Metzora Parashat Zavim, Section 5 9), בלא עת נדתה OUT OF THE TIME OF HER SEPARATION — i. e. at least three days immediately after the seven normal days of her separation have expired. או כי תזוב OR IF SHE HAS A FLOW during these (the above mentioned) three days, על נדתה BEYOND THE TIME OF HER SEPARATION — i. e. being remote (distant) from her time of separation by one intervening day — this woman (such a woman) is, in both cases, termed a זבה and the law regarding her is decreed in this section that follows; and it is not like the law of a נדה, because she (the former) requires the counting of seven clean days (i. e. her uncleanness does not end until she has counted שבעה נקיים, seven consecutive days that are clean of any flux; cf. v. 28) and a sacrifice on the following day (cf. v. 29); whilst the נדה does not require the counting of the clean days (i. e. התורה ‎מן nor does she require a sacrifice) but she remains seven days in her separation and no longer irrespective as to whether she has or has not seen a show of blood (i. e. even if there is a flow on the seventh day and it then ceases she is still clean on the eighth day after having immersed herself). And they (our Rabbis) in expounding this section in the Sifra explain. There are eleven days intervening between the end of one ,נדה-period and the beginning of the next נדה-period, so that if she sees blood on three immersed herself. And they (our Rabbis) in expounding this section (Sifra, Metzora Parashat Zavim, Chapter 8 2-3) derived the Halacha of the eleven days that intervene between the expiration of one נדה period and the commencement of another ‎נדה period — i. e. that as a result of any three consecutive days that she sees blood within these eleven days she shall be (come under the law of) a זבה and not a נדה.

וְאִשָּׁ֡ה כִּֽי־יָזוּב֩ ז֨וֹב דָּמָ֜הּ יָמִ֣ים רַבִּ֗ים בְּלֹא֙ עֶת־נִדָּתָ֔הּ א֥וֹ כִֽי־תָז֖וּב עַל־נִדָּתָ֑הּ כׇּל־יְמֵ֞י ז֣וֹב טֻמְאָתָ֗הּ כִּימֵ֧י נִדָּתָ֛הּ תִּהְיֶ֖ה טְמֵאָ֥ה הִֽוא׃

And if a woman have an issue of her blood many days not in the time of her menstruation, or if it run beyond the time of her menstruation; all the days of the issue of her uncleanness shall be as the days of her menstruation: she shall be unclean.