amygdala

Etymology

It is borrowed from Latin amygdala (“almond”),^[2][3][1][4] which Merriam-Webster Unabridged and Etymonline describe as New Latin or as from Latin amygdalum,^[5][6] from Ancient Greek ἀμυγδάλη (amugdálē, “almond”).^{[2][3][7][6][8]} The anatomical use comes from Medieval Latin, where the word also meant a tonsil;^[6][8][9] Klein and Etymonline explain this as a translation of an Arabic expression meaning "the two tonsils", literally "the two almonds", used by Arabic physicians because of the likeness in shape.^[7][6] The Latin word had earlier given Old English amigdal (“almond”),^[10][11][2] and the Middle English plural amygdales, the tonsils, is recorded from the early 15th century;^[6][2] the Shorter Oxford notes that some uses and the form amygdale come from French.^[4] The same Greek word is the source of almond.^[6][5][7]

Earliest recorded meaning

A tonsil, usually in the plural: 1749, in Barrow's medical dictionary.^[2] Merriam-Webster Unabridged dates this sense to 1731.^[5]

Semantic evolution

The Latin word for the almond was applied to parts of the body thought to resemble the nut in shape.^[6][1] In English it first meant the tonsils;^[2][5] from 1845 it also meant a rounded lobe on the underside of each hemisphere of the cerebellum;^[2][5] both senses are now rare or obsolete.^[2] From 1889, first in the Century Dictionary, it named an almond-shaped mass of grey matter in each cerebral hemisphere, one of the basal ganglia,^[2][5] which Stedman's describes as assigning emotional value to sensory input;^[8] this is now the usual sense.^[4]

Timeline

• 1749 – a tonsil, usually in the plural.^[2] Merriam-Webster Unabridged dates this sense to 1731.^[5]
• 1845 – a lobe on the underside of each hemisphere of the cerebellum.^[2]
• 1889 – an almond-shaped mass of grey matter in each cerebral hemisphere of the brain.^[2]

Meanings

Noun

1. An almond-shaped mass of grey matter deep in each temporal lobe of the brain, one of the basal ganglia, involved in emotion, motivation and fear: Damage to the amygdala dulled his sense of danger.^[5][2][8]
2. (anatomy) An almond-shaped part, such as a tonsil of the throat or a rounded lobe on the underside of the cerebellum; now rare in these senses.^[5][12][2]

Word family

• amygdalic

Related words

• amygdalin
• amygdaloid
• almond
• amygdale
• mandorla

Usage notes

The plural is amygdalae.^[5][12][4]

References

1. ^ a b c Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l m n Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
4. ^ a b c d Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
5. ^ a b c d e f g h i j Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
6. ^ a b c d e f g Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
7. ^ a b c Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
8. ^ a b c d Stedman's Medical Dictionary, Baltimore: Lippincott Williams & Wilkins
9. ^ Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
10. ^ Bosworth, Joseph; Toller, T. Northcote (1898), An Anglo-Saxon Dictionary, Oxford: Clarendon Press; Toller, T. Northcote (1921), Supplement
11. ^ Holthausen, Ferdinand (1934), Altenglisches etymologisches Wörterbuch, Heidelberg: Carl Winter
12. ^ a b Collins English Dictionary (2023), Glasgow: HarperCollins