Final answer:
The compositional technique that imitates or represents real-world sound is sonic art or soundscape composition.
Step-by-step explanation:
The compositional technique that attempts to imitate or represent real-world sound is sonic art or soundscape composition. This artistic approach involves using sound elements to create an immersive auditory experience that reflects or mimics the sounds found in the natural or human-created environment. Sonic art can be found in various forms, such as music, installations, performances, and recordings, where artists manipulate and organize sounds to evoke specific emotions or convey messages.