In this article, nanostructured ultrawideband absorber is proposed for infrared to ultraviolet spectrum. The proposed three layered absorber structure formed of nickel, polyimide and nickel (Ni) material. The proposed unit cell volume is 90nm × 90 nm × 10.62 nm (0.0484λL× 0.0484λL× 0.00571λLnm3 where, λL is wavelength at lowest operating frequency). Absorption (A)≥ 90 % is achieved from 161.48 THz (1857.81 nm) to 3894.58 THz (77.03 nm) which covers infrared, visible and ultraviolet frequency bands. The average absorption 98.08 % is achieved over the entire operating frequency band. The absorption is also analyzed in different resonating patch geometry and using different substrate material. Due to the symmetricity of the octagonal patch geometry, the proposed structure is polarization insensitive and has incident angle (θ◦) stability up to 60° for absorption more than 80 %. The proposed solar absorber achieves 96.82 % solar absorption efficiency (ηA) and also achieves 94.61 %, 95.78 %, 96.31 % & 96.62 % thermal emission efficiency (ηE) at temperature 2000K, 2500K, 3000K & 3500K respectively. The suggested nanostructure absorber design works well across infrared, visible, and ultraviolet (UV) light, making it an efficient absorber for various uses like solar panels, detectors, solar energy harvesters, thermal devices, cloaking, solar power, sensors, and UV protection.