n. In ancient Rome and the Roman empire, a companion of or attendant upon a great person; hence, the title of an adjutant to a proconsul or the like, afterward specifically of the immediate personal counselors of the emperor, and finally of many high officers, the most important of whom were the prototypes of the medieval counts. See count.n. [ML.] In early and medieval usage, a book containing the epistles to be used at mass; an epistolary; more specifically, the ancient missal lectionary of the Roman Church, containing the epistles and gospels, and said to have been drawn up by St. Jerome.n. [NL.] In music, the repetition of the subject or “dux” of a fugue by the second voice at the interval of a fourth or fifth. Also called consequent, or answer.n. [NL.] In anatomy, a vessel accompanying another vessel or other structure.n. In astronomy, a small companion star in any double, triple, or multiple ‘system.’