astronomical expert (archaic title)
Archaic title for an official astronomer or astrologer in the ancient Japanese court system. Cross-referenced with 天文博士 (てんもんはかせ).
See also: 天文博士
Reidairō was a government post in the ancient imperial court responsible for astronomy.
From Chinese-derived terms 霊台 (spirit platform/observatory) and 郎 (official title suffix). The exact historical derivation is uncertain.