Trope

A category of plainchant that flourished from the 10th through the 12th centuries, comprising musical and textual additions fo the established repertory of Mass (both Proper and Ordinary) and Office chants.

The methods of interpolation are now often desiganated as: (a) the addition of a new text to a melisma of a traditional "Gregorian" chant; (b) the composition of a new melody and text, which is then sung together with a traditional chant in various ways, before and/or after it, or by alternation of the phrases of the trope with those of the original chant, or, in the case of a short text like the "Benedicamus Domino", embedding the few original words or their synonyms in an elaborate new melody and text; (c) an independently composed melody without text added to an item of the standard repertory.

According to Grout, a trope was originally a newly composed addition, usually in neumatic style and with a poetic text, to one of the antiphonal Chants of the Proper of the Mass (most often to the Introit, less often to the Offertory and Communion); later, such additions were made also to Chants of the Ordinary (especially the Gloria). The earliest tropes served as prefaces to the regular chant; at a later stage, tropes are found also in the form of interpolations between the lines of a chant.

The terms "trope" and "troping" have often been used in an extended sense to designate all additions and interpolations to the chant, thus including the sequence, for example, as a subclass under "tropes."