To punctuate means to add marks like periods, commas, question marks, and exclamation points to writing. These marks, called punctuation, help readers understand where sentences begin and end, where to pause, and what tone the writer intends. Without punctuation, writing becomes confusing: “Let's eat Grandma” means something very different from “Let's eat, Grandma!”

A misplaced comma can change your entire meaning. “I love cooking, my family, and my dog” makes it sound like you're listing three things you love, while “I love cooking my family and my dog” suggests something alarming.

The word also means to interrupt or emphasize something repeatedly. Thunder might punctuate a stormy night. A speaker might punctuate her speech with dramatic pauses. A comedian punctuates his routine with funny voices. When something punctuates an event, it marks important moments or breaks things up, just like punctuation marks break up sentences.

Good punctuation is almost invisible when done right. Readers don't notice it; they just understand your meaning clearly. But when it's wrong or missing, everything becomes harder to follow.