sul·​fate | \ ˈsəl-ˌfāt How to pronounce sulfate (audio) \

Definition of sulfate

 (Entry 1 of 2)

1 : a salt or ester of sulfuric acid
2 : a divalent group or anion SO4 characteristic of sulfuric acid and the sulfates


sulfated; sulfating

Definition of sulfate (Entry 2 of 2)

transitive verb

: to treat or combine with sulfuric acid or a sulfate

Examples of sulfate in a Sentence

Recent Examples on the Web: Noun

Look for products labeled sulfate-free, like L'Oréal Paris' EverPure pair. Leah Melby Clinton, Marie Claire, "Color Your Hair? Four Things You Should Never Do in the Shower," 16 Nov. 2018 Aerosols are made of sea salt, rock dust, organic material from plants and conglomerations of sulfate molecules. Helen Czerski, WSJ, "Tiny Particles That Let You See Your Breath," 11 Oct. 2018 Most importantly, look for shampoos that are sulfate free to really help your color last. Zoë Weiner, Teen Vogue, "Lucy Hale Debuted Blonde Hair," 10 Oct. 2018 Under the Sun products are also sulfate free, which work best on my hair, leaving it less weighed down, bouncy, and free. Noel Cymone Walker, SELF, "7 Lessons I Learned the Hard Way Wearing My Hair Natural at the Beach," 25 Sep. 2018 But when exposed to air again, the iron sulfides react with oxygen to produce sulfate salts and sulfuric acid, which eat away at the already fragile timbers and artifacts where wood is in contact with iron. Kiona N. Smith, Ars Technica, "Tiny magnets will escort ions out of rare material from a shipwreck," 24 Aug. 2018 Traditional high-pH soap and sodium lauryl sulfate (SLS) are stripping surfactants; milder ones include sodium laureth sulfate (SLES), decyl glucoside, coco-glucoside, and others. Allure, "The Skin-Care Glossary: A Comprehensive Guide to Everything You Need to Know," 17 Aug. 2018 The lightweight serum is all-natural and free of parabens, sulfates and fragrances. Olivia Hall, The Seattle Times, "Overstressed? 15 wellness trends to help you relax," 3 July 2018 Around 2010, a public dialogue regarding sulfates (cheap lathering detergents) entered the soap lexicon. Tyler Watamanuk, New York Times, "When Did Soap, Once Simple, Get So Complicated?," 11 July 2018

Recent Examples on the Web: Verb

The team also found that sulfated anophelins are more effective than hirudin, a blood-thinning molecule derived from the salivary juices of leeches, which is occasionally used in clinical settings. Vanessa Zainzinger, Science | AAAS, "Mosquito spit can bust blood clots in mice," 10 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sulfate.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of sulfate


1788, in the meaning defined at sense 1


1888, in the meaning defined above

History and Etymology for sulfate


French, from Latin sulfur

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Time Traveler for sulfate

The first known use of sulfate was in 1788

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English Language Learners Definition of sulfate

chemistry : a salt that is formed when sulfuric acid reacts with another chemical element


variants: or chiefly British sulphate \ ˈsəl-​ˌfāt How to pronounce sulphate (audio) \

Medical Definition of sulfate

 (Entry 1 of 2)

1 : a salt or ester of sulfuric acid
2 : a bivalent group or anion SO4 characteristic of sulfuric acid and the sulfates


transitive verb
variants: or chiefly British sulphate
sulfated or chiefly British sulphated; sulfating or chiefly British sulphating

Medical Definition of sulfate (Entry 2 of 2)

: to treat or combine with sulfuric acid or a sulfate

More from Merriam-Webster on sulfate

Nglish: Translation of sulfate for Spanish Speakers Encyclopedia article about sulfate

Comments on sulfate

What made you want to look up sulfate? Please tell us where you read or heard it (including the quote, if possible).


to corrupt or become corrupted

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