Lewis & Short

instĭtūtum, i, n. [instituo], a purpose, intention, design; an arrangement, plan; mode of life, habits, practices, manners; a regulation, ordinance, institution; instruction; agreement, stipulation (class.): ejus omne institutum voluntatemque omnem successio prospera consecuta est, Cic. Hortens. Fragm.: ad hujus libri institutum illa nihil pertinent, id. Top. 6: me nunc oblitum consuetudinis et instituti mei, id. Att. 4, 18: meretricium, id. Cael. 20, 50: majorum, id. Agr. 2, 1: vitae capere, to form a plan of life, id. Fin. 4, 15, 40: juris publici leges et instituta, id. Brut. 77: instituta Parthorum, Tac. A. 6, 32: institutis patriae parere, Nep. Ages. 4: praecepta institutaque philosophiae, Cic. Off. 1, 1: optimis institutis mentem infantium informare, Quint. 1, 1, 16.
Adv.: ex instituto, according to law or tradition: militem ex instituto dare, Liv. 6, 10, 6; 45, 13, 8.