diagonalize

especially British, di·ag·o·nal·ise

[dahy-ag-uh-nl-ahyz, -ag-nl-]

verb (used with object)

diagonalized, diagonalizing 

1. Mathematics.,  to transform (a matrix) to a diagonal matrix.

Word History and Origins

Origin of diagonalize¹

First recorded in 1880–85; diagonal + -ize