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diagonalize

American  
[dahy-ag-uh-nl-ahyz, -ag-nl-] / daɪˈæg ə nlˌaɪz, -ˈæg nl- /
especially British, diagonalise

verb (used with object)

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


Etymology

Origin of diagonalize

First recorded in 1880–85; diagonal + -ize