meridian quadrant
/mɪˌrɪdɪən ˈkwɒdr(ə)nt/noun
1 Astronomy. A quadrant fixed to a wall lying in the plane of the meridian; a mural quadrant. Compare mural. Now historical.
2The distance from the north pole to the equator along a meridian (being a quarter of the earth's circumference).
Origin
Late 18th century; earliest use found in Philosophical Transactions of the Royal Society of London. From meridian + quadrant, after post-classical Latin quadrans meridianus.