Uncontrolled nodding

The Collaborative International Dictionary Word definitions in The Collaborative International Dictionary
Nutation \Nu*ta"tion\, n. [L. nutatio a nodding, fr. nutare to nod: cf. F. nutation.] The act of nodding. So from the midmost the nutation spreads, Round and more round, o'er all the sea of heads. --Pope. (Astron.) A very small libratory motion of ...

Wikipedia Word definitions in Wikipedia
In engineering , a nutating motion is similar to that seen in a swashplate mechanism. In general, a nutating plate is carried on a skewed bearing on the main shaft and does not itself rotate, whereas a swashplate is fixed to the shaft and rotates with it. ...

Wiktionary Word definitions in Wiktionary
n. 1 (context physics English) a bobbing motion that accompanies the precession of a spinning rigid body 2 a nodding motion (of the head etc.) 3 (context astronomy English) any of several irregularities in the precession of the equinoxes caused by varying ...

WordNet Word definitions in WordNet
n. uncontrolled nodding

Douglas Harper's Etymology Dictionary Word definitions in Douglas Harper's Etymology Dictionary
1610s, "action of nodding," from Latin nutationem (nominative nutatio ), noun of action from past participle stem of nutare "to nod," from PIE *neu- "to nod" (see numinous ). Astronomical use is from 1715. Related: Nutational .