oscillate (part of speech: verb)
- In a general way a cable keeps a ship anchored in the same place, although wind and waves may cause it to " librate" about the anchor. - "A Text-Book of Astronomy", George C. Comstock.
- He proceeded to see if by making the planet librate, or the plane of its orbit tilt up and down, anything could be done. - "Pioneers of Science", Oliver Lodge.