2011_11_20 mitigate \MIT-i-geyt\, verb: To become milder; lessen in severity.

mitigate \MIT-i-geyt\, verb:
1. To lessen in force or intensity, as wrath, grief, harshness, or pain; moderate.
2. To make less severe: to mitigate a punishment.
3. To make (a person, one's state of mind, disposition, etc.) milder or more gentle; mollify; appease.
4. To become milder; lessen in severity.
I owe you a thousand obligations for all the attention you showed me in my late calamitous situation, and ill, very ill, should I repay those obligations, if I did not try as a friend to mitigate these violent transports.
 -- Charlotte Turner Smith, Celestina
That does nothing to mitigate your condescending arrogance.
 -- William Kittredge, The Willow Field
Mitigate is from the Latin roots mit (soft) and agere (to cause).