Added 10 October 2026 fosterage noun Categories: LanguageActionsObscure Words noun ! Definition from Wiktionary (CC BY-SA). More about fosterage at Wordnik → Where our words come from → The act of fostering another's child as if it were one's own. The act of caring for another human being or animal. The condition of being the foster child. Related Words: fosteringupbringingrearingnurtureraisingbreedingnurturingfosterhoodfosterlingfosterer Back to today's word