tensor

Etymology

It is borrowed from New Latin tensor,^{[2][3][4][5][6]} an agent noun^[2][3] from Latin tēnsus, the past participle of tendō (“to stretch”),^[4][5][6] with the suffix -or.^[6][4] Dictionary.com glosses the New Latin word "stretcher".^[7] Etymonline traces the verb to Proto-Indo-European *ten- (“to stretch”).^[3] The Shorter Oxford takes the mathematical sense as formed after vector.^[8]

Earliest recorded meaning

A muscle that stretches or tightens a part of the body: 1704, in Harris's Lexicon Technicum.^[2][4][3] Dictionary.com dates the word to 1695–1705.^[7]

Semantic evolution

The anatomical word was taken into mathematics by W. R. Hamilton in 1846, in his theory of quaternions, for a quantity expressing the ratio by which the length of a vector is increased;^[2][8] the Shorter Oxford marks that use obsolete.^[8] The modern sense, an abstract entity represented by an array of components that are functions of coordinates and change in a set way when the coordinates are transformed, is recorded from 1916, in the Monthly Notices of the Royal Astronomical Society.^[2] Merriam-Webster describes such a tensor as a generalized vector with more than three components.^[6][9]

Timeline

• 1704 – a muscle that stretches or tightens a part.^[2][4][3]
• 1846 – in quaternions, the ratio by which a vector's length is increased.^[2]
• 1916 – an array of components that transform in a set way under a change of coordinates.^[2]

Meanings

Noun

1. (anatomy) A muscle that stretches or tightens a part of the body; also called a tensor muscle.^[10][6][2]
2. (mathematics) A set of components, functions of the coordinates of a point in space, that transform linearly from one coordinate system to another; a generalization of a vector.^[10][6][2]
3. (mathematics, obsolete) In quaternions, the quantity giving the ratio by which a vector's length is increased.^[2][8]

Word family

• tensorial

Related words

• tense
• tend
• tension
• extensor
• vector

References

1. ^ a b Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b c d e Barnhart, Robert K. (1988), The Barnhart Dictionary of Etymology
5. ^ a b The American Heritage Dictionary of the English Language (online 2024), 5th ed., Boston: Houghton Mifflin Harcourt
6. ^ a b c d e f Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
7. ^ a b Dictionary.com Unabridged (2016), based on the Random House Unabridged Dictionary, New York: Random House
8. ^ 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
9. ^ Merriam-Webster's Collegiate Dictionary (2003), 11th ed., Springfield, Mass.: Merriam-Webster
10. ^ a b Collins English Dictionary (2023), Glasgow: HarperCollins