Is ‘vector’ not an old term?

Question

According to Merriam-Webster, the mathematical sense of ‘vector’ dates from 1941. I can’t believe this. Is it true?

https://www.merriam-webster.com/dictionary/vector

Answer 1

Your link states 1941 is the earliest known use of the verb version of the word, but it traces the noun to 1846. This isn't far off Servaes's figure.

Answer 2

Merriam Webster traces the word back to 1846, and the closely related 'radius vector' to 1740.

According to wikipedia, the words 'vector', 'scalar' and 'tensor' were introduced by Sir William Rowan Hamilton. The word 'vector' is used without further explanation in his treatise on quaternions of 1853, suggesting in was in common usage by then (in the field, at least).

Answer 3

The "Earliest Known Uses of Some of the Words of Mathematics" site has a lengthy entry about "vector" and related terms. It appears that some context of the word traces back to 1704, although the term as we tend to think of it today was introduced (along with "scalar") by Hamilton in 1844. Here are a few paragraphs from the entry. (Emphasis mine.)

VECTOR, VECTOR ANALYSIS and VECTOR SPACE. The entries below follow changes in the use of the term vector over the past 150 years or so. The story begins with a technical term in theoretical astronomy, "radius vector," in which "vector" signified "carrier." In the first and biggest change "radius" was dropped and "vector" was given a place in the algebra of quaternions (c. 1840). The recognition that vectors are more interesting than quaternions, especially in physics, led to vector analysis (c. 1880). In the 20th century vector was extended from triples of numbers to n-tuples and then to elements of abstract linear spaces.

The word VECTOR (which, like the word vehicle, derives ultimately from the Latin vehĕre to carry) was first a technical term in astronomical geometry. The OED’s earliest entry is from a technical dictionary of 1704: J. Harris Lexicon Technicum I. s.v., "A Line supposed to be drawn from any Planet moving round a Center, or the Focus of an Ellipsis, to that Center or Focus, is by some Writers of the New Astronomy, called the Vector; because 'tis that Line by which the Planet seems to be carried round its Center."

[...]

VECTOR and SCALAR. Both the terms vector and scalar were introduced by William Rowan Hamilton (1805-1865).

Both terms appear in "On quaternions" a paper presented by Hamilton at a meeting of the Royal Irish Academy on November 11, 1844.

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