wag

A dog wags its tail when it's happy, moving it side to side in a show of excitement. But "wag" is not just for tails. In some places, it is an informal way to say someone is avoiding duty, like a student who "wags school" and skips class. It can also describe any quick, repeated motion, like a loose tooth moving back and forth before it finally falls out.

Think of a playful puppy's tail or a child trying to get out of chores. The idea is usually a quick back-and-forth motion, sometimes happy and sometimes avoiding something. You might wag a finger at someone in disapproval, or say that "tongues are wagging" when people are gossiping.

To wag means to move something back and forth rapidly, often side-to-side. The most common image is a dog wagging its tail—a classic sign of happiness or friendliness. "The puppy wagged its tail so hard its whole body wiggled!"

However, "wag" has expanded far beyond tails. It describes various repetitive, swinging motions. A loose tooth might wag in your mouth, or a person might wag a finger to admonish someone. Informally, particularly in British, Australian, and New Zealand English, "to wag" means to evade duty or responsibility, such as "wagging school" (skipping class). This usage stems from the idea of "shaking off" an obligation.

The word also appears in vivid idioms. If "tongues are wagging," it means people are gossiping. You might also hear the phrase "wag the dog," which refers to purposefully creating a distraction to divert attention from a more important or scandalous issue. While a 1997 movie popularized the term, the idiom comes from the idea of a tail being so large and powerful that it wags the dog, rather than the other way around.

Finally, "wag" can also be a noun referring to a person who is a bit of a joker or a wit. So, whether it's a happy tail, a bit of gossip, or a clever prankster, "wag" describes movement and character that is either literal and playful or figurative and evasive.