What term describes a word on a line by itself at the end of a paragraph?

The term that describes a word on a line by itself at the end of a paragraph is known as a "widow." A widow occurs when a single word or very short phrase is left hanging on its own line, which can disrupt the flow and aesthetics of text.

This typographic concept is important for technical writing, as clarity and formatting are crucial for effective communication. Understanding terms like "widow" helps writers maintain better control over how their written content appears, ensuring that it is visually appealing and easy to read. In contrast, the other terms do not accurately describe the situation; for example, "orphan" refers to a similar concept but applies to a single word or line that appears at the beginning of a new paragraph instead of the end. "Paragraph" is a general term for a distinct section of text, and "single line" lacks the specific context needed to describe the typographical issue at hand.