Lewis & Short

instīgātĭo, ōnis, f. [instigo], an urging, stimulating, instigating, an incitement, instigation: auditorum, Auct. Her. 2, 30, 47: novercalibus instigationibus corrupti, Dig. 5, 2, 4: praedonum, Lact. 5, 19, 2.