This word is mostly in medical use, to describe some abnormal way of walking or of holding oneself, usually as a symptom of a cerebral or spinal disease.
This tremor was interesting not only because it involved his hands and his head, so-called titubation, but because it soon became apparent that when the politician had to concentrate or felt uneasy, the nodding head was momentarily stilled.
The Times, 21 Jan. 1983.
It comes directly from the Latin verb titubare, which could mean “stutter” as well as “stumble”, and this former meaning occasionally surfaced in English, though it is long since obsolete.
Outside medicine, titubation has been used facetiously to refer to unsteadiness brought on by too much of the demon drink, though this wasn't the implication in the report in The Times.