|1.||astronomy a periodic variation in the precession of the earth's axis causing the earth's poles to oscillate about their mean position|
|2.||physics a periodic variation in the uniform precession of the axis of any spinning body, such as a gyroscope, about the horizontal|
|3.||Also called: circumnutation the spiral growth of a shoot, tendril, or similar plant organ, caused by variation in the growth rate in different parts|
|4.||the act or an instance of nodding the head|
|[C17: from Latin nutātiō, from nūtāre to nod]|
nutation nu·ta·tion (nōō-tā'shən, nyōō-)
The act of nodding the head, especially involuntarily.