tōa-lāu-bú大老母

father's primary wife

father's primary wife (in relation to children of concubines or other wives)

English Wiktionary, “大老母” (CC BY-SA 4.0) — https://en.wiktionary.org/wiki/%E5%A4%A7%E8%80%81%E6%AF%8D · confidence: Medium (Wiktionary)