Nanometric silicon carbide (SiC) powder (similar to 5nm) with a stacking-sequence disordered structure (SD-SiC), synthesized from elemental powders of Si and C, was investigated by microscopic and several spectroscopic methods. The structure of SD-SiC was characterized by transmission electron microscopy (TEM), C-13, and Si-29-NMR, and by infrared (IR), Raman, and X-ray photoelectron spectroscopy (XPS) methods. TEM characterizations showed relatively large deviations of the lattice parameters in the as-synthesized SiC, indicative of the presence of stacking-sequence disorder. IR analysis showed a weaker Si-C bond in the SD-SiC than in the 3C-SiC. XPS determinations showed that C and Si in SD-SiC are similar to those in 3C-SiC. Broader peaks of Si-29 and C-13 MAS-NMR also indicate that the structure of SD-SiC is different from that of 3C-SiC. Raman spectroscopy exhibited activities for the crystalline polytypes and the amorphous of SiC but lack of them for the SD-SiC. The inactivity of Raman spectroscopy for the SD-SiC along with large deviation of the lattice constant and the extremely broad X-ray diffraction peaks would indicate that SD-SiC is a possible intermediate state between conventional polytype SiC and amorphous SiC, that is, a possible new type of SiC.