the GNU version of the Collaborative International Dictionary of English
verb-intransitive. To swing as a pendulum.
The Century Dictionary and Cyclopedia
To hang or swing freely; swing; dangle; vibrate as a pendulum.
Word Usage
"Sure, it's traditional for Americans to vote either Dem or Repug, just as in Canada we perilously pendulate between the lookalike Fibs and ConArtists, but IT'S A FALSE TRADITION."