Non-integer-dimensional architected materials enabling synergistic acoustic, mechanical, and fluid coupling

stress redistribution, and enhanced airflow efficiency enabled by drag-reducing multiscale channels. These functionalities arise intrinsically from fractal hierarchy, without reliance on material heterogeneity or external hybridization. Crucially, the dimensional parameter serves as a scalable and fabrication-accessible handle, bridging abstract fractional geometry with real-world engineering. This work establishes NDAMs as a powerful design axis for next-generation multifunctional metamaterials, with potential applications in aerospace, transport, and biomedical systems.