Mahāprajāpatī Gautamī

Mahāprajāpatī Gautamī (Sanskrit: महाप्रजापती गौतमी; Pali: Mahāpajāpatī Gotamī) or simply Prajāpatī was the foster-mother, step-mother and maternal aunt (mother's sister) of the Buddha. Therefore, based on the Therī-apadāna (Mahāpajāpatigotamī-therīapadāna, Thi Ap 17), Gotamī is referred to by the title "Mother of the Buddha" (Pali: Buddhamātā). In Buddhist tradition, she was the first woman to seek ordination for women, which she did from Siddhartha Gautama directly, and she became the first bhikṣuṇī (Buddhist nun).

Source: Wikipedia — https://en.wikipedia.org/wiki/Mah%C4%81praj%C4%81pat%C4%AB_Gautam%C4%AB