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Synonyms

diametrically

British  
/ ˌdaɪəˈmɛtrɪkəlɪ /

adverb

  1. completely; utterly (esp in the phrase diametrically opposed )

"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

Explanation

If one thing is the exact opposite of something else, they're diametrically opposed. Here, diametrically is used to mean "totally" or "completely." Diametrically is an unusual word — it's only used to modify the adjective opposed. When you describe two things that couldn't be more different from each other, you can say they're diametrically opposed. Is your brother a cheerful, optimistic person, while your sister is cranky and gloomy? Then they're diametrically opposed. This word comes from diameter, a line through a circle, in the sense that two points at either end of a diameter are directly opposite each other.

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Vocabulary lists containing diametrically

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.

Is it possible to prevent an heir from spending their inheritance on things to which we are diametrically opposed?

From MarketWatch • Feb. 16, 2026

"There are members of Brics+ that are diametrically opposed to each other politically and even have hot border skirmishes between them," defence analyst Dean Wingrin told the BBC.

From BBC • Jan. 9, 2026

But Donaldson sees these videos as pragmatic; making money and promoting charitable causes, he and his team would argue, are not diametrically opposed.

From The Wall Street Journal • Jan. 3, 2026

But Fabbro’s wistful salute to bygone traditions has significant limitations, especially noticeable in the reductive design of his diametrically opposed main characters.

From Los Angeles Times • Nov. 14, 2025

Whether even a heroic level of leadership stood any chance was uncertain because—and here was the cruelest irony—the effort to make the Revolution truly complete seemed diametrically opposed to remaining a united nation.

From "Founding Brothers: The Revolutionary Generation" by Joseph J. Ellis