Pyrex
"pyrex" is a 5-letter English headword indexed on PlainSpell.
The verdict
“Pyrex” is uncommon English (frequency #52,577 among 46,516 “P” headwords), classed as a proper noun. The kind of spelling people second-guess.
- #52,577
- frequency rank, English
- 46,516
- “P” headwords
According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - A brand of glassware produced by the Corning corporation, capable of resisting high temperatures, and suitable for cooking applications, currently made with tempered glass.
| Property | Value |
|---|---|
| Headword | Pyrex |
| Language | English |
| Part of speech | Proper noun |
| Letters | 5 |
| Frequency rank | #52,577 |
| Misspellings tracked | 0 |
| Confusable pairs | 0 |
| Source | Wiktionary (kaikki.org) |
Where “Pyrex” sits in English frequency
Rare enough to double-check
Pyrex is uncommon English at frequency #52,577 among 46,516 “P” headwords, classed as aproper noun. Rarity is why readers land here mid-draft. 2 senses are on record.
The misspelling generator found no plausible variants for Pyrex, and the word's spelling is regular enough that our generator found nothing worth flagging. This entry stands alone in our confusable dataset, since nothing in our dataset looks or sounds close enough to cause mix-ups.
Etymologically, the entry records: From pie + r + -ex. First manufactured by the Corning Glassware Factory in 1915. * 1957, Letter from the Corning Glassware Factory: *: "We had a number of prior trademarks ending in the letters ex. One of the first commercial products to be sold under the n… The correct English form is Pyrex, spelled P-Y-R-E-X.
Definition
- 1A brand of glassware produced by the Corning corporation, capable of resisting high temperatures, and suitable for cooking applications, currently made with tempered glass.
- 2A brand of glassware produced by Corning using borosilicate glass.
Etymology
From pie + r + -ex. First manufactured by the Corning Glassware Factory in 1915. * 1957, Letter from the Corning Glassware Factory: *: "We had a number of prior trademarks ending in the letters ex. One of the first commercial products to be sold under the new mark was a pie plate, and in the interests of euphonism the letter "r" was inserted between pie and ex, and the whole thing condensed to pyrex." * The name also connotes the fire of pyro-.
Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.
Frequently Asked Questions
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Using “Pyrex”
The practical upshot for anyone who landed here from a spell-check.
- The one correct English spelling is P-Y-R-E-X - every other letter order is a misspelling in standard orthography.
- Browse more English words and confusable pairs in the same reference. English words
Other uncommon English words near this rank
Data Source
Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.