Angrboða is a Jötunn, wife of Loki, and mother of Jörmungandr, Fenrir and Hel. While she's never mentioned, Jörmungandr's Jötunn Shrine specifically names her in Elder Futhark: "ᚨᛝᚱᛒᛟᚦᚨ". It's possible that she survived the genocide of the giants by Aesir gods since both of her sons Jörmungandr and Fenrir are alive and well even though her present whereabouts are currently unknown.