Mus. The fourth tone in the Guidonian hexachord on Fut; B-flat at intervals of a second below middle C and a seventh above middle C. …

(a) A written communication, a letter; (b) a letter of authority or credentials; an authorization. …

Mus. (a) The lowest tone in the hexachordal scale; (b) the entire hexachordal system. …

Mus. The third note in a Greek tetrachord. …

Mus. A note intermediate between the semibreve and the crotchet, prob. equivalent to a modern half-note. [See also minute n.(2).] …

Mus. ?The hypodorian mode. …

Mus. An interval approximating half a whole tone. …

(a) An interval or a span of time elapsing between two specified points, events, etc.; (b) the amount or extent of time comprised by or contained within a specified period; -- often with gen. or of ph……

Mus. The first note or degree of Guido d’Arezzo’s hexachords; ut la; ef fa ut; ge-sol-re ut, q.v. …