Word.ws English Dictionary

R99

R99 noun: r99 standard.

Noun

R99 (countable and uncountable, plural R99s)

  1. (uncountable) R99 standard
  2. (countable) R99 filter

Forms of R99

pluralR99s

Origin of R99

From Initialism of Resistant to oil particles with 99% filtration efficiency in NIOSH air filtration ratings.

Questions about R99

What does R99 mean?
R99 means r99 standard.
What part of speech is R99?
R99 is a noun.
What is the plural of R99?
The plural of R99 is R99s.

Words near R99 in the dictionary

  1. R34
  2. r8
  3. R9
  4. R95
  5. R95s
  6. R99
  7. R99s
  8. ra
  9. Ra's al Khaymah
  10. Ra's at Tib
  11. Ra's Tannurah

Source and license

Adapted from Wiktionary: R99 (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

Last updated:

Cite this entry: “R99.” Word.ws, https://word.ws/r99. Based on Wiktionary, CC BY-SA 4.0.