principally Copy link Outline I. In the highest degreeII. In the main, for the most part • principally: I. In the highest degree: maxĭmē, praecĭpuē, etc.: v. particularly, especially. II. In the main, for the most part: Phr.: they live p. on milk and cattle, maximam partem lacte atque pecore vivunt, Caes. B. G. 4, 1: see also mostly.