Final answer:
The expressive device used by Renaissance composers to musically illustrate the text is known as word painting, a predominant feature in Renaissance music that aligns musical elements with the narrative of the text.
Step-by-step explanation:
The expressive device that Renaissance composers used to pictorialize words musically is called word painting. This technique involves composing the music in a way that musically illustrates the meaning of the words in the text, enhancing the listener's experience and understanding of the content. Renaissance music often employed word painting to depict vivid imagery through the music itself, whether it was imitating bird calls, ascending scales for rising action, or dramatic melodies to highlight tense emotions. Example of this can be seen in the motets of Cyprien de Rore, where the musical elements would align closely with the textual narrative. Additionally, the blend of melody, harmony, and rhythm in Renaissance music aimed to create a cohesive and expressive soundscape that would bring the text to life.