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topic sentence

American  
Or topical sentence

noun

  1. a sentence that expresses the essential idea of a paragraph or larger section, usually appearing at the beginning.


topic sentence British  

noun

  1. a sentence in a paragraph that expresses the main idea or point of the whole paragraph

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

topic sentence Cultural  
  1. The main sentence in a paragraph, often the first sentence. It briefly conveys the essential idea of the paragraph.


Etymology

Origin of topic sentence

First recorded in 1915–20

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

But crafting a note like “A topic sentence should signal what the paragraph is about. Can you try reworking this sentence to reflect the paragraph?” is far more empowering.

From Scientific American • Jun. 15, 2023

Does the topic sentence make a sensible point?

From Textbooks • Dec. 21, 2021

Check that each paragraph has a topic sentence that states the main idea of the paragraph.

From Textbooks • Dec. 21, 2021

To perform this check, copy and paste to a new page one topic sentence and the sentences that develop it.

From Textbooks • Dec. 21, 2021

Where, in such paragraphs, is the topic sentence?

From English: Composition and Literature by Webster, W. F. (William Franklin)