take the edge off
Ease or assuage, make less severe, as in That snack took the edge off our hunger, or Her kind manner took the edge off her refusal. This term alludes to blunting the edge of a cutting instrument. Shakespeare used it figuratively in The Tempest (4:1): "To take away the edge of that day's celebration." The precise wording of the idiom dates from the first half of the 1900s.