characteristic root

Etymology
, the term preferred by French mathematician (1789–1857).

Noun

 * 1)  An eigenvalue.
 * 2) * 1962 [Prentice Hall], Leonard E. Fuller, Basic Matrix Theory, 2017, Dover, page 217,
 * There is an important relationship between the characteristic roots of a symmetric matrix and the r and p of the associated quadratic form. It is true that the number of positive characteristic roots is p, whereas the number of nonzero characteristic roots is r.
 * 1) * 2009, Babu Ram, Engineering Mathematics, Pearson Education India, page 13.56,
 * Theorem 13.54. The characteristic roots of a Hermitian matrix are real.
 * Theorem 13.54. The characteristic roots of a Hermitian matrix are real.