What is the history of the term "tensor"?

Look at the bottom of page 2 and top of page 3 of Conrad's "Tensor Products" paper for a discussion of the early usage of the term "tensor" in physics and mathematics.

Here is a brief historical review of tensor products. They first arose in the late 19th century, in both physics and mathematics. In 1884, Gibbs [4, Chap. 3] introduced the tensor product of vectors in $\mathbf R^3$ under the label "indeterminate product"$^*$ and applied it to the study of strain on a body. Gibbs extended the indeterminante product to $n$ dimensions two years later [5]. Voigt used tensors for a description of stress and strain on crystals in 1898 [14], and the term tensor first appeared with its modern meaning in his work.$^\dagger$ Tensor comes from the Latin tendere, which means "to stretch." In mathematics, Ricci applied tensors to differential geometry during the 1880s and 1890s. A paper from 1901 [12] that Ricci wrote with Levi-Civita (it is available in English translation as [8]) was crucial in Einstein's work on general relativity, and the widespread adoption of the term "tensor" in physics and mathematics comes from Einstein's usage; Ricci and Levi-Civita referred to tensors by the bland name "systems." In all of this work, tensor products were built out of vector spaces. The first step in extending tensor products to modules is due to Hassler Whitney [16], who defined $A \otimes_{\mathbf Z} B$ for any abelian groups $A$ and $B$ in 1938. A few years later Bourbaki's volume on algebra contained a definition of tensor products of modules in the form that it has essentially had ever since (within pure mathematics).

$^*$The label indeterminate was chosen because Gibbs considered this product to be, in his words, "the most general form of product of two vectors," as it was subject to no laws except bilinearity, which must be satisfied by any operation on vectors that deserves to be called a product.

$^\dagger$Writing $\mathbf i$, $\mathbf j$, and $\mathbf k$ for the standard basis of $\mathbf R^3$, Gibbs called any sum $a\mathbf i\otimes\mathbf i + b\mathbf j\otimes\mathbf j + c\mathbf k\otimes\mathbf k$ with positive $a$, $b$, and $c$ a right tensor [4, p. 57], but I don't know if this had any influence on Voigt's terminology.