Nutation

2 definitions found

From The Collaborative International Dictionary of English v.0.48 [gcide]:

  Nutation \Nu*ta"tion\, n. [L. nutatio a nodding, fr. nutare to
     nod: cf. F. nutation.]
     1. The act of nodding.
        [1913 Webster]
  
              So from the midmost the nutation spreads,


              Round and more round, o'er all the sea of heads.
                                                    --Pope.
        [1913 Webster]
  
     2. (Astron.) A very small libratory motion of the earth's
        axis, by which its inclination to the plane of the
        ecliptic is constantly varying by a small amount.
        [1913 Webster]
  
     3. (Bot.)
        (a) The motion of a flower in following the apparent
            movement of the sun, from the east in the morning to
            the west in the evening.
        (b) Circumnutation.
            [1913 Webster]

From WordNet (r) 2.0 [wn]:

  nutation
       n : uncontrolled nodding