1.NounA vector that is only scaled (not rotated out of its span) under a particular linear transformation; a left or right eigenvector depending on context; given a linear transformation A, a vector x such that Ax=λx [or xA=λx] for some scalar λ (called the eigenvalue).
2.NounA right eigenvector; given a matrix A, the eigenvector of the transformation "left-side multiplication by A."