LAHN (plural alhan)
Arabic translation of Coptic /,oc, adopted from Greek ekhos, a term used in Coptic liturgical books and manuscripts to specify the music to be sung to a given text. Sometimes translated into English as “air,” “tone,” “melody,” or “mode,” it refers basically to either a certain melody or melody type that is readily recognized by the people and known by a specific, often descriptive name, such as Lahn al-Farah (. . . of joy) and Lahn al-Huzn (. . . of sorrow).
Two leading Alhan to be cited as melody types are ADAM and WATUS. Lahn may have some affinities yet to be elucidated with the Byzantine echos and the Arabic maqam. For a more complete discussion, see MUSIC: DESCRIPTION OF THE CORPUS, and MUSIC: HISTORY.