unidimensional

relating to a single dimension or aspect; having no depth or scope; "a prose statement of fact is unidimensional, its value being measured wholly in terms of its truth"- Mary Sheehan; "a novel with one-dimensional characters"

रेखा (लकीर) एकायामी वस्तु होती है क्योंकि इसकी केवल लम्बाई होती है, न कोई चौड़ाई न कोई मोटाई !

A line is unidimentional physical quantity as it has only length, no width, no thickness.