In the broadest sense tropes are all the later musical and textual accretions to the Franco-Roman nucleus of antiphonal and responsorial chants for mass and offices that we call Gregorian chant, a repertoire primarily fixed by the early 9th century. A trope might be a newly added textless melody (a melisma), text added to a preexistent melisma (a prosula), or newly composed text and melody added to an older item as an introduction or interpolation (a trope per se).

In the month of Magha, a vessel laid anchor in the harbour of this town.

But a negro servant who had been stationed as warden at the door refused to allow the messenger to pass in, saying, 'The gemman can't be disturbed.'

On board, groomers, commissary, and flight attendants work diligently.