Rationalize

01 v. t. To make rational; also, to convert to rationalism.

1.
To make rational; also, to convert to rationalism.
2.
To interpret in the manner of a rationalist.
3.
To form a rational conception of.
4.
To render rational; to free from radical signs or quantities.(Alg.)

02 v. i. To use, and rely on, reason in forming a theory, belief, etc., especially in matters of religion: to accord with the principles of rationalism.

1.
To use, and rely on, reason in forming a theory, belief, etc., especially in matters of religion: to accord with the principles of rationalism.
“Theodore . . . is justly considered the chief rationalizing doctor of antiquity.” — J. H. Newman.