nutation
Concise Oxford English Dictionary © 2008 Oxford University Press:
nutation /njuːˈteɪʃ(ə)n/
▶noun
- 1 a periodic variation in the inclination of an axis of rotation, especially that causing the earth's precession to follow a wavy rather than a circular path.
- 2 Botany the circular swaying movement of the tip of a growing shoot.
– origin C17 (denoting nodding of the head): from L. nutatio(n-), from nutare ‘to nod’.
'nutation' also found in these Oxford entries:
