Lewis & Short

2. instinctus, ūs, m. [instinguo], instigation, impulse (class.; mostly in abl. sing.): oracula, quae instinctu divino afflatuque funduntur, inspiration, Cic. Div. 1, 18, 34; id. ib. 1, 6 fin.; 1. 31, 66: sine caelesti aliquo mentis instinctu, id. Tusc. 1, 26: instinctu decurionum, Tac. H. 1, 70: instinctibus daemonum, Lact. 4, 30: ex instinctu deorum dicere, Mos. et Rom. Leg. Coll. 15, 2, 5.