The main line about which a rotating body or structure is organized or arranged.

The main reference line in a graph or chart that shows the primary relationship between two variables.

प्राथमिक संदर्भ रेखा

English Usage: On the graph, the primary axis represents the quantity of items sold.

Hindi Usage: ग्राफ पर, प्राथमिक धुरी बेचे गए वस्तुओं की मात्रा को दर्शाती है।