Estrild is the Medieval English form of Middle English Éastorhild; the second element comes from Old English hild (battle, war) while the first part of the name comes from Eostre, the name of a Germanic goddess of spring and fertility. The origin of the name comes from Proto-Germanic *Austrǭ (Easter, springtime) derived from PIE root word *h₂ews- (dawn; east). Estrildis is the name of a captured Germanic princess according to Geoffrey of Monmouth’s pseudohistorical tales of British history in the 12th century. She was the mistress of Locrinus, a king of the Britons, who kept her and their daughter Sabrina hidden in a cave till the death of his father-in-law which gave him the chance to leave his wife and son for her. It turned out to be a bad move when his scorned wife assembled an army that met his in battle in which he was killed and Estrildis and Sabrina were drowned in a river.
- Estrildis (Latinized Medieval English)