in medieval music, a metrical Latin song of ceremonial character for one, two, or three voices. The word first appeared in mid-12th-century manuscripts with reference to processional pieces.

In the 13th century the conductus was one of three genres that dominated French polyphonic music. Unlike the organum and the motet, however, which were based on preexisting chants, the conductus was a freely composed setting of a single metrical Latin text. Of particular importance for future developments was its homophonic texture (all voices moving at the same rhythmic rate or, from the modern perspective, “chordally”), which offered welcome points of departure for the Burgundian polyphonists of the 15th century.

The 13th-century commentator Franco of Cologne distinguished between conductus cum and sine littera (with and without words); while the former was in simple syllabic style, the latter was not only untexted but, in some instances, quite florid in nature and hence suitable for use as caudae (singular cauda), extended lively passages inserted into relatively unadorned compositions.