plural respirators
1
: a mask or device worn over the mouth and nose to protect the respiratory system by filtering out dangerous substances (such as dusts, fumes, or bacteria) from inhaled air

Note: Particulate respirator masks are only able to filter out particles and are not effective against gases or vapors. A numerical rating (such as 95 or 99) is sometimes assigned to such a respirator to indicate the percentage of airborne particles filtered. A letter may also be assigned to indicate whether it is somewhat resistant (R), not resistant (NR), or strongly resistant (P) to the degrading effects of oil on proper respirator function.

2
: a device for maintaining artificial respiration : ventilator sense b

Examples of respirator in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
When outdoors, consider wearing an N95 mask or P100 respirator marked with NIOSH, per the Michigan Department of Environment, Great Lakes and Energy. Jenna Prestininzi, Freep.com, 20 July 2026 My husband also hates using the respirator and will rarely wear it. Judith Martin, Sun Sentinel, 18 July 2026 Anyone who becomes dizzy or has trouble breathing while wearing a respirator should move to cleaner air and remove the mask. Anthony Thompson, USA Today, 17 July 2026 There are no commercially available respirators that protect against all of the dangerous pollutants in wildfire smoke. Noah Haggerty, Los Angeles Times, 2 July 2026 See All Example Sentences for respirator

Word History

First Known Use

1836, in the meaning defined at sense 1

Time Traveler
The first known use of respirator was in 1836

Cite this Entry

“Respirator.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/respirator. Accessed 27 Jul. 2026.

Kids Definition

respirator

noun
1
: a device covering the mouth and nose especially to prevent the breathing in of harmful substances (as dust or fumes)
2
: a device used to maintain artificial respiration

Medical Definition

respirator

noun
1
: a mask or device worn over the mouth and nose to protect the respiratory system by filtering out dangerous substances (as dusts, chemical fumes, or bacteria) from inhaled air

Note: Particulate respirator masks are only able to filter out particles and are not effective against gases or vapors. A numerical rating (such as 95 or 99) is sometimes assigned to a particulate respirator to indicate the percentage of airborne particles filtered. A letter may also be assigned to indicate whether it is somewhat resistant (R), not resistant (NR), or strongly resistant (P) to the degrading effects of oil on proper respirator function.

2
: a device for maintaining artificial respiration : ventilator

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