词源 |
nutation n.1610s, "action of nodding," from Latin nutationem (nominative nutatio), noun of action from past participle stem of nutare "to nod," from PIE *neu- (2) "to nod" (see numinous). Astronomical use in reference to slight periodical oscillation of the earth's axis is from 1715. Related: Nutational. updated on July 20, 2019 |