带状 is an attributive adjective (attr.) meaning 'band-shaped' or 'strip-like'. It's used in technical or descriptive contexts — geography (带状区域 'strip-shaped area'), medicine (带状疱疹 'shingles', literally 'band-shaped herpes'), or any situation where something has a long, narrow, ribbon-like form. It cannot stand alone as a predicate; it always modifies a noun.