1. a long thin bar with a weight at the lower end that swings from side to side, usually in order to keep a clock working
2. the pendulum (of something): used for talking about the tendency of an opinion or situation to change from one position or condition to its opposite
Origin and usage
The word pendulum is a noun derived from the Latin ‘pendulus’ which means hanging down. By the mid 17th century, pendulum was used in reference to an object that swings from one point to another freely.
A pendulum is a weighted object that is hung from a specific point, which swings to and fro under the force of gravity. A pendulum is often found inside a clock where it functions as a timekeeper. Pendulum can also be used to describe opinions or circumstances that change regularly, for example, public opinion can sway like a pendulum on various topics.
When two clocks with a pendulum mechanism are hung together side by side, over time their swinging movement becomes synchronized. This phenomenon puzzled clock makers for hundreds of years until 2015 when a team of Portuguese scientists conducted a series of experiments using two pendulum clocks. They discovered that sound pulses create energy which is transferred between clocks and eventually this energy causes each pendulum to move at the same time.
“The pendulum of the mind oscillates between sense and nonsense, not between right and wrong.”
(Carl Gustav Jung)
“At first glance it is simply a clock, a rather large black clock with a white face and a silver pendulum. Well crafted, obviously, with intricately carved woodwork edges and a perfectly painted face, but just a clock. But that is before it is wound. Before it begins to tick, the pendulum swinging steadily and evenly.”