Lewis Short
nūtātĭo (noun F) : id. (post-Aug.).
* A nodding: capitis,Plin. 11, 37, 49, § 135.
* A swaying.
* Lit.: frequens et in utramque partem nutatio,Quint. 11, 3, 129.
* Trop., a shaking, tottering: nutatio reipublicae,Plin. Pan. 5, 6.
Charlton T. Lewis, Charles Short, A Latin Dictionary