platelet

Etymology

It is formed from English plate + -let, a small plate.^{[2][3][4][5][6][7]} Merriam-Webster Unabridged treats it as a formation of the International Scientific Vocabulary.^[8] In its sense in physiology it follows German Blutplättchen or French petite plaque du sang, the terms used by G. Bizzozero in 1882;^[2] English had earlier used “blood plate”, plaque and plaquette for the same thing.^[2]

Earliest recorded meaning

A small or minute plate, in various senses: 1879, in the Marion (Ohio) Daily Star.^[2]

Semantic evolution

The word soon specialized in physiology for the small colourless discs in mammalian blood, also called blood platelets, first in 1888 in M. Foster's Text Book of Physiology;^[2] Merriam-Webster Unabridged also dates the word to 1888.^[8] Etymonline, which dates it to 1895, calls this its original and main use,^[4] and Dictionary.com dates the word to 1890–95.^[6] Collins notes that platelets were formerly called thrombocytes;^[7] Merriam-Webster Unabridged gives both names and explains that they are fragments of the cytoplasm of megakaryocytes.^[8]

Timeline

• 1879 – a small or minute plate.^[2]
• 1888 – a small disc in the blood of mammals that helps it to clot.^[2][8] Etymonline dates the word to 1895.^[4]

Meanings

Noun

1. A tiny colourless disc-shaped body without a nucleus, found in large numbers in the blood of mammals, which helps the blood to clot; a thrombocyte: The test showed a low platelet count.^[7][8][2][3]
2. A minute flat body or plate, as of ice or a mineral.^[8][2][3]

Related words

• plate
• plaque
• plaquette

References

1. ^ Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
4. ^ a b c Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
5. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
6. ^ a b Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
7. ^ a b c Collins English Dictionary (2023), Glasgow: HarperCollins
8. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster