duplum

…a simple second melody (duplum) to an existing plainchant melody (the vox principalis, or principal voice), which by the end of the 12th century was stretched so as to accommodate a melody.

1 (Lat.). In two parts; used in medieval polyphony to describe a composition for two voices, e.g. organum duplum.

Organum duplum is two-part organum that sets the solo sections of responsorial chants from either the Offices or the Mass. An elaborate and charismatic upper voice weaves intricate patterns above the appropriate plainchant, which is sung in extended note values by the lower voice, or 'tenor'.

Leonin Organum Duplum Leonin's name is tied to the organum duplum or organum for two voices. This style offers more freedom to performers than the three-voice and four-voice organa. Many works of organum duplum, organum triplum, and organum quadruplum are found in the Magnus Liber Organi.

In 12th century organum, the duplum was the part immediately above the tenor. If a third part was present, it was called the triplum.

The Roman law stated that if someone caused harm to another person's property, they would have to pay "in duplum" of the value of the property. The examples illustrate the use of the term "in duplo" in legal contexts.

For example, should the consumer borrow R10 000, end up owing interest and costs of another R11 000 and repay only R3 000 of the capital, the maximum amount that could be recovered would be the unpaid capital of R7 000 together with interest and costs up to a maximum of a further R7 000.

The Roman law stated that if someone caused harm to another person's property, they would have to pay "in duplum" of the value of the property. The examples illustrate the use of the term "in duplo" in legal contexts.

Organum (/ˈɔːrɡənəm/) is, in general, a plainchant melody with at least one added voice to enhance the harmony, developed in the Middle Ages.

More specifically, the word organum refers to a polyphonic style of sacred chanting that flourished in Europe from 8th to 13th century and the term melismatic indicates a vocal line in which there are several notes sung on the same syllable (melisma).

Organum purum or organum per se refers to sustained-tenor passages of organum duplum where no particular modal rhythm is apparent (free rhythm).

Literally translated, in duplum means 'double the amount'. This common law rule provides that interest on a debt will cease to run where the total amount of arrear interest has accrued to an amount equal to the outstanding principal debt.