Definition & Meaning of "em dash"

What is an "em dash"?

An em dash (—) is a punctuation mark that is longer than both a hyphen (-) and an en dash (–). It is often used to create a strong break in a sentence or to set off information for emphasis. For example, in the sentence "She was late—again," the em dash adds emphasis to the fact that lateness is a recurring issue. Em dashes can also be used to insert additional thoughts or clarifications, as in "He finally answered the question—after thinking for a long time." Unlike commas or parentheses, em dashes provide a more pronounced interruption in the flow of writing, allowing for a more dramatic effect. They are versatile punctuation marks that enhance readability and add style to writing.