Lewis & Short

dēfensĭto, āvi, 1, v. a. freq. [defenso], to defend often, to practise defending (perh, only in the foll. passages): haec non acrius accusavit in senectute, quam antea defensitaverat, Cic. Ac. 2, 22; cf. ib. 2, 45, 139: causas, id. Brut. 26, 100; id. Off. 1, 33 fin.