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Synonyms

seriously

American  
[seer-ee-uhs-lee] / ˈsɪər i əs li /

adverb

  1. in a serious manner.

    He shook his head seriously.

  2. to an alarmingly grave extent.

    seriously ill.

  3. with genuine, earnest intent; sincerely.

    Seriously, kids, we have to get home before dark.
seriously British  
/ ˈsɪərɪəslɪ /

adverb

  1. in a serious manner or to a serious degree

  2. informal extremely or remarkably

    seriously tall
"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

Etymology

Origin of seriously

First recorded in 1500–10; serious + -ly

Explanation

When you do something seriously, you do it earnestly or thoughtfully. If you seriously consider walking the Appalachian Trail, it means that you put real effort and thought into contemplating such a trip. If your boss speaks seriously to you, you know she means what she's saying, and if you think seriously about what a fortune teller told you, it means that you really consider what she said your future might bring. You can also use seriously to mean significantly, or to a worrying degree, like being seriously ill with the flu. Informally, seriously also means very or truly, like when you are seriously hungry.

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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.

Seriously, see for yourself — it’s currently streaming on Netflix.

From Salon • Mar. 28, 2026

"She masters that American absolutely beautiful accent that she does," Mielewska, who worked with Byrne on the 2022 comedy "Seriously Red", told AFP at her home in Sydney's leafy north.

From Barron's • Mar. 5, 2026

"Seriously, I am there for two hours because I am so proud," he beams.

From BBC • Feb. 15, 2026

Seriously, there’s a pretty large gap between what voters would like to see happen and what a governor — any governor — can plausibly deliver.

From Los Angeles Times • Feb. 8, 2026

Seriously, I have no idea where Mr. Neely finds all his excitement, but I wish I could siphon some of it off and give it to Mom.

From "The Science of Breakable Things" by Tae Keller

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.