tensor

The story

1. German · borrowed fromTensor
2. New Latin · borrowed fromtensor“that which stretches”
3. English todaytensor

Borrowed from New Latin tensor (“that which stretches”), equivalent to tense + -or. Anatomical sense from 1704. Introduced in the 1840s by William Rowan Hamilton as an algebraic quantity unrelated to the modern notion of tensor. The contemporary mathematical meaning was introduced (as German Tensor) by Woldemar Voigt (1898) and adopted in English from 1915 (in the context of general relativity), obscuring the earlier Hamiltonian sense. The mathematical object is so named because an early application of tensors was the study of materials stretching under tension. (See, for example, Cauchy stress tensor on Wikipedia.Wikipedia )

First known use, by meaning

• from 17th c. A muscle that tightens or stretches a part, or renders it tense.
• from 18th c. A mathematical object that describes linear relations on scalars, vectors, matrices and other algebraic objects, and is represented as a multidimensional array.
• from 18th c. A multidimensional array with (at least) two dimensions.