Musannaf Ibn Abi Shayba 28:1129

Waki’ narrated to us, he said: Al-Walid ibn ‘Abd Allah ibn Jumay’ narrated to us, he said: My grandmother narrated to me, and ‘Abd Allah ibn Khallad al-Ansari, from Umm Waraqah bint Nawfal, that when the Prophet, peace and blessings of Allah be upon him, went out to [the battle of] Badr, she said: I said, "O Messenger of Allah, permit me to go out with you to fight, so that I may treat your wounded and nurse your sick, perhaps Allah will grant me martyrdom." He said: "Stay in your house, for Allah will grant you martyrdom." She said: And she used to be called "the martyr."