Lo tenemos chicos. Cuando utilizas una parte de la melodía de una canción y la regrabas a tu manera, se llama "interpolation" (el ejemplo actual más claro es el On the Floor. Lo de Beyoncé en Run The World, en cambio, es un sample porque coge directamente la pista original).
In popular music
Interpolation has been used by one artist to refer to the addition of new material in a performance or recording of a previously existing piece of music.
In rap music
In rap music, interpolation refers to using a melody – or portions of a melody (often with modified lyrics) – from a previously recorded song, but re-recording the melody instead of sampling it.
