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Synonyms

radically

American  
[rad-ik-lee] / ˈræd ɪk li /

adjective

  1. with regard to origin or root.

  2. in a complete or basic manner; thoroughly; fundamentally.


radically British  
/ ˈrædɪkəlɪ /

adverb

  1. thoroughly; completely; fundamentally

    to alter radically

"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

Other Word Forms

  • nonradically adverb

Etymology

Origin of radically

First recorded in 1600–10; radical + -ly

Explanation

The adverb radically is a great way to say "in an extreme way." When your formerly long-haired friend shows up at work with a crew cut, you could say that she looks radically different. Use radically to describe things that are done in a big way, particularly a change or an extreme position. For example, the government in your state might change radically after an important election. You'll often see the phrase "radically different" used to mean a change that's enormous, possibly even transforming. Though the root of radically, radical, originally meant "root of a word," it came to mean "far-reaching, innovative, or extreme," especially when it describes political views.

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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.

Before you take the leap, know that your level of happiness may not change as radically as you think.

From MarketWatch • Apr. 10, 2026

“When I see an ICE agent doing something radically bad and harmful, I can recognize that that is a person who is suffering and being oppressed by a deep darkness.”

From Salon • Apr. 6, 2026

But even readers without religious commitments may be interested in the stories of how and why some people change their lives so radically, often at a considerable cost.

From The Wall Street Journal • Apr. 3, 2026

Since the 2000s the city's planners have been preoccupied with building more utilitarian infrastructure, with new sea bridges and coastal roads, radically transforming how the city looks today.

From BBC • Apr. 3, 2026

The second book, A Preliminary Discourse on the Study of Natural Philosophy, published in 1830 by the astronomer Sir John Herschel, suggested a radically different view.

From "The Gene" by Siddhartha Mukherjee