mitigation — the act of mitigating, or lessening the force or intensity of something unpleasant, as wrath, pain, grief, or extreme circumstances: Social support is the most important factor in the mitigation of stress among adolescents.
justification — a reason, fact, circumstance, or explanation that justifies or defends: His insulting you was ample justification for you to leave the party.
qualification — a quality, accomplishment, etc., that fits a person for some function, office, or the like.
moderation — the quality of being moderate; restraint; avoidance of extremes or excesses; temperance.
apology — An apology is something that you say or write in order to tell someone that you are sorry that you have hurt them or caused trouble for them.
explanation — A statement or account that makes something clear.
reduction — the act of reducing or the state of being reduced.
abatement — Abatement means a reduction in the strength or power of something or the reduction of it.
diminution — the act, fact, or process of diminishing; lessening; reduction.
