Ḥilm is the ability to remain measured rather than react angrily; ḥikmah is choosing what is appropriate, fair, and effective in context. The two often reinforce one another.
When two colleagues disagree, avoiding harsh words reflects forbearance. Hearing both sides and seeking a just solution reflects wisdom. Self-control is incomplete if the decision remains unjust, and correct information helps little when applied cruelly.
عَثْرَةٍ means a lapse and تَجْرِبَةٍ experience. Both appear in the genitive as complements of ذُو.