Becoming A Bhikkhuni
The progression to ordination as a Bhikkhuni is taken in four steps. A lay person may take the five upāsikā (Pali and Sanskrit; masculine: upāsaka; Tibetan dge snyan ma, pronounced genyenma, "approaching virtue") vows. The next step is to enter the pabbajja (Srt: pravrajya, Tib. rab byung pronounced rabjung), or monastic way of life, which includes wearing monk's or nun's robes. After that, one can become a samaneri (Pali; feminine: samanera; Skt. śrāmaṇera/śrāmaṇeri, Tib. dge tshul/dge tshul ma, pronounced getshül/getshülma), or novice monk/nun. The last and final step is to take all the vows of a bhikkhuni (Sanskrit: Bhikṣu/Bhikṣuṇī, Tib. dge long/dge long ma, pronounced gelong/gelongma) a "fully ordained nun."
According to the vinaya, a bhikkhuni, unlike a bhikkhu, should not be accepted by the sangha to take these vows again in one life after "giving them back". So she cannot be a buddhist nun again.
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