Antonyms for the phrase "touching off" include "calming down," "soothing," "reassuring," and "pacifying." These antonyms represent actions and emotions that are the opposite of the explosive, sparking connotations of "touching off." Instead, these antonyms describe actions and emotions that seek to de-escalate situations and bring peace. For example, in a heated argument, one might use calming words or a reassuring tone to pacify the other person and prevent the situation from escalating. Similarly, in a tense political climate, leaders may seek to soothe tensions and reassure the public that everything is under control.