a sentence in a paragraph that expresses the main idea or point of the whole paragraph
topic sentence in American English
the principal sentence, setting forth the main idea and coming usually at the beginning, in a paragraph or section of a discourse, esp. of an expository nature
Examples of 'topic sentence' in a sentence
topic sentence
What is the topic sentence of paragraph 2?
Goshgarian, Gary Exploring language (6th edn) (1995)
Let's look at some short paragraphs that lack topic sentences.
Bachmann, Susan (editor) & Barth, Melinda Between Worlds: A Reader, Rhetoric and Handbook (1995)