dull the edge of (something)

dull the edge of (something)

To lessen some aspect of something, often so that it is less severe or effective. Unfortunately, there is little we can do to dull the edge of such an emotional issue.
See also: dull, edge, of

dull the edge of

make less sensitive, interesting, or effective.
The image here is of making a knife's edge blunt.
See also: dull, edge, of