[precession of the equinoxes] (1621): a slow westward motion of the equinoxes along the ecliptic caused by the gravitational action of sun and moon upon the protuberant matter about the earth's equator
PRECESSION OF THE EQUINOXES
Meaning of PRECESSION OF THE EQUINOXES in English
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012