Make (plans) definite (7)
I believe the answer is:
confirm
(Other definitions for confirm that I've seen before include "Provide support for the truth" , "Ratify; establish" , "Substantiate" , "Philosophy of life" , "Corroborate" .)
I believe the answer is:
confirm
(Other definitions for confirm that I've seen before include "Provide support for the truth" , "Ratify; establish" , "Substantiate" , "Philosophy of life" , "Corroborate" .)