cossist

cossist

English

Etymology

From Italian cossista, from the word cosa, "thing", in reference to an unknown quantity to be determined + -ista. See rule of coss.

Noun

cossist (plural cossists)

1. (historical) A practitioner of proto-algebra in Renaissance and Early Modern Europe.
   • 2005. Amir D. Aczel, Descartes' Secret Notebook: A True Tale of Mathematics, p. 121.

     The word "cossist" comes from the Italian cosa, meaning "thing." The cosa was the mystery that algebra was designed to solve -- it was the name given to the unknown quantity in an equation (our modern x).

   • 2014. L. E. Sigler, Leonardo Pisano (Fibonacci): The Book of Squares, p. xvii.

     So also were trained the Cossists and Rechenmeister of Germany in his tradition.

Adjective

cossist (not comparable)

1. Pertaining to the cossists and their methods; cossic.
   • 1989. Chikara Sasaki, Descartes's Mathematical Thought, p. 90.

     Clavius's treatise is, first of all, reckoned as one of the textbooks of cossist algebra.

   • 2018. Michael Sean Mahoney, The Mathematical Career of Pierre de Fermat, 1601-1665), p. 5.

     Cossist algebra constituted essentially a sophisticated form of arithmetical problem-solving. Often it is difficult when reading a cossist text to discern where computational arithmetic leaves off and algebra begins.