commentarius
σιγᾶν ἄμεινον ἢ λαλεῖν ἃ μὴ πρέπει → it's better to keep silence than to say what's not appropriate (Menander)
Latin > English (Lewis & Short)
commentārĭus: ii, m. (sc. liber;
I both together, Gell. 13, 20, 17); commentā-rĭum, ii, n. (sc. volumen, Varr. L. L. 6, § 90 Müll.; Cic. Brut. 44, 164; cf. commentariolum) commentor.
I Orig. a note-book, sketch-book, memorandum: diurni, a journal, Suet. Aug. 64.—
II As the title of a book on any subject, but esp. historical, which is only sketched down or written without care (mostly in plur.), a sketch, a paper, memoirs, a commentary, etc., Cic. Fam. 5, 12, 10; Liv. 42, 6, 3; Quint. 2, 11, 7; 3, 8, 58; 3, 8, 67; 8, 2, 12; 10, 7, 30 al.; Tac. A. 6, 47; Suet. Tib. 61 et saep. Thus the two works of Cæsar upon the Gallic and civil wars are called Commentarii, commentaries, Cic. Brut. 75, 262; Hirt. and Asin. Pollio ap. Suet. Caes. 56.—Of a single book: superiore commentario, i. e. in the Seventh Book, Hirt. B. G. 8, 30; cf. Gai Inst. 2, 23; 2, 145.—
B Esp.
1 A commentary, exposition, brief explanation, annotation: commentarium in Vergilium, Gell. 2, 6, 1; cf. id. 1, 12; 1, 21.—
2 In law, a brief, Cic. Verr. 2, 5, 21, § 54.—
3 The day-book of an accounting officer, Inscr. Grut. 592, 4; Inscr. Orell. 2904.—
4 A collection of examples or citations, Quint. 1, 8, 19.—
5 A pupil's notes of a lecture or lesson, Quint. 3, 6, 59.