rex

Etymology

It is borrowed from Latin rēx (“king, sovereign ruler”),^[2][3][4][5] genitive rēgis,^[3][4] related to regō (“to keep straight, guide, rule”) and rēgīna (“queen”).^[3][4] It comes from Proto-Indo-European *reg- (“to move in a straight line, hence to direct, rule”),^[3][4][6] which is shared with Old Irish rí (“king”),^[3][4] and in other forms with the Gaulish elements behind rich and the Sanskrit source of raja.^[2] The name of the animal coat is the same Latin word: the American Heritage Dictionary takes it through French lapin rex (“rex rabbit”), the name of a rabbit breed developed in France between 1919 and 1924,^[6] and Merriam-Webster through New Latin.^[5]

Earliest recorded meaning

To act in a lordly way, in the phrase to play rex: the OED dates its entry from this record, in J. Ponet's treatise on political power of 1556.^[2] It also records the word as a title or inscription from an early Old English charter of Berhtwulf of Mercia, and notes that Old English manuscripts apparently sometimes wrote it for Old English cyning (“king”).^[2] As a plain noun for "king", Etymonline dates it to the 1610s and the Shorter Oxford to the early 17th century.^[3][7]

Semantic evolution

In English the word has lived mostly as a Latin title, placed after a king's name on coins and documents.^[8][2] From the early 18th century, in law reports, it stood for the reigning king as the prosecutor in criminal cases.^[2][7] In the 16th century the phrase to play rex or to play the rex meant to domineer, a use that the OED follows until 1822.^[2] Merriam-Webster also records it for the presiding masquer at a Mardi Gras festival, as at New Orleans.^[5] The 20th-century sense began with a rabbit: the breed name, meaning "king", was then extended to mice and rats, and to cats with short curly coats.^[6][2][7]

Timeline

• 1556 – to play rex: to act in a lordly way, to domineer (obsolete after 1822).^[2]
• 1566 – with plural agreement, pranks, tricks, chiefly with play (obsolete after 1732).^[2]
• 1610s – a king.^[3]
• before 1715 – with a capital, the reigning king as the prosecution in criminal proceedings.^[2]
• 1920 – an animal coat with very short or absent guard hairs.^[5] The OED's first quotation for the rabbit is from 1928.^[2]
• 1953 – adjective, of an animal, that is a rex.^[2]
• 1958 – a breed of cat with a short curly coat.^[2] The Oxford Dictionary of English dates the cat to the 1960s.^[9]

Meanings

Noun

1. A king, especially as part of the official title of a reigning king, used after the name on coins, in inscriptions and in documents.^[8][9][2]
2. Usually Rex: the Crown as prosecutor in criminal proceedings when the monarch is a king: Rex vs Harris.^[7][9][2]
3. Usually Rex: the presiding masquer of a Mardi Gras festival or parade.^[5]
4. An animal coat, resulting from a genetic mutation, in which the guard hairs are very short, wavy or missing.^[5][6][7]
5. A rabbit, cat or other animal with such a coat; often a cat of a breed with curly fur.^{[6][9][10][2]}
6. (obsolete, 1566–1732) With plural agreement: pranks, chiefly in to play rex.^[2][5]

Adjective

1. Of an animal, especially a rabbit or cat: that is a rex.^[2][5]

Verb

1. To breed animals such as rabbits selectively so as to establish the rex coat.^[5]

Word family

• Cornish Rex
• Devon Rex

Related words

• regina
• regal
• royal
• regent
• regulus
• raj
• ranee
• viceroy

Usage notes

The plural of the title is reges,^[5][11] that of the animal rexes or rex.^[5] The title is abbreviated R.^[10] The obsolete "pranks" sense has a disputed source: Merriam-Webster calls it of unknown origin,^[5] while the OED calls it uncertain, compares reak, and says it may be an extended use of to play rex or may have a different origin, with its spelling due to association with the title.^[2] In Scottish dialect rex or rexa-boxa-king was a playground game in which a player called the King calls out to the others.^[12]

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l m n o p q r s t Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e f g Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b c d e Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
5. ^ a b c d e f g h i j k l Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
6. ^ a b c d e The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
7. ^ a b c d e Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
8. ^ a b Collins English Dictionary (2023), Glasgow: HarperCollins
9. ^ a b c d Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
10. ^ a b The Chambers Dictionary (2014), 13th ed., Edinburgh: Chambers
11. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
12. ^ Wright, Joseph, ed. (1898–1905), The English Dialect Dictionary, 6 vols., Oxford: Henry Frowde; via EDD Online 4.0, University of Innsbruck (CC BY 4.0)