zeal·​ous ˈze-ləs How to pronounce zealous (audio)
: marked by fervent partisanship for a person, a cause, or an ideal : filled with or characterized by zeal
zealous missionaries
zealously adverb
zealousness noun

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Zealous vs. Jealous

Zealous and jealous share not just a rhyme, but an etymology. Both words ultimately come from the Latin zelus “jealousy,” and in the past their meanings were somewhat closer to each other than they are today. In the 16th and 17th centuries, zealous occasionally was used in biblical writing to refer to a quality of apprehensiveness or jealousy of another. By the 18th century, however, it had completely diverged in meaning from jealous, signifying “warmly engaged or ardent on behalf of someone or something.” Today, zealous often carries a connotation of excessive feeling: it typically means “fiercely partisan” or “uncompromisingly enthusiastic.”

Example Sentences

I was zealous in my demands on my sisters for promptness in rehearsals. I was passionate, intolerant of small talk, hungry for knowledge, grabby, bossy, precocious. Lynn Margulis, Curious Minds, (2004) 2005
Sir Thomas was zealous in the pursuit of recusants, not poachers, and was otherwise an amiable man. S. Schoenbaum, Shakespeare's Lives, 1991
Zealous in his ministerial labours, blameless in his life and habits, he yet did not appear to enjoy that mental serenity, that inward content, which should be the reward of every sincere Christian and practical philanthropist. Charlotte Brontë, Jane Eyre, 1847
He had no cause for self-reproach on the score of neglect, or want of thought, for he had been devoted to her service; and yet a hundred little occasions rose up before him, on which he fancied he might have been more zealous, and more earnest, and wished he had been. Charles Dickens, Oliver Twist, 1838
The detective was zealous in her pursuit of the kidnappers.
Recent Examples on the Web But in practice, these gatekeepers are often too zealous, slowing the passage of ions they are meant to let sail through, which saps device performance. Byrobert F. Service, science.org, 26 Apr. 2023 Her whole life was in front of her and it was taken from her by racist, under trained, over zealous, lying cops. Jonathan Edwards, Washington Post, 25 Apr. 2023 Even then, in some cases there are multiple options, such as the Salt Lake City area, where Ikon has five resorts with 7-days each and one unlimited, and that’s enough for even the most zealous. Larry Olmsted, Forbes, 16 Mar. 2023 That would increase if the Fed goes too far with rate hikes, but Baker doesn’t think Powell will get too zealous. Tori Otten, The New Republic, 1 Feb. 2023 These immigrants, the ones who weren’t brought here in chains, turned entrepreneurial, disordered, antic, religiously zealous, morally charged, messianic, and perpetually restless. David Brooks, The Atlantic, 31 Oct. 2022 Under the leadership of a zealous priest, who started conducting human sacrifice rituals after experiencing a religious vision, people are dying out. Marta Balaga, Variety, 5 Apr. 2023 Given the circumstances, this case has the feel of zealous prosecutors minutely examining all possibilities to find some violation of the law. Fareed Zakaria, CNN, 2 Apr. 2023 During the trial, prosecutors described her as a zealous election denier who orchestrated violence inside the building, while Ulrich depicted her as a naive young woman who made an error in judgment by joining the mob. Paul Duggan, Washington Post, 23 Mar. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'zealous.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of zealous was in the 15th century

Dictionary Entries Near zealous

Cite this Entry

“Zealous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/zealous. Accessed 10 Jun. 2023.

Kids Definition


zeal·​ous ˈzel-əs How to pronounce zealous (audio)
: filled with or showing zeal : marked by passionate support for a person, cause, or ideal
zealously adverb
zealousness noun

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