Leonardo da Vinci designed a spinning machine to make textile work more efficient by twisting thread.
Spinning turns loose fibres such as wool or flax into a continuous yarn by drawing out and twisting the fibres. Leonardo’s notebooks contain mechanical studies of textile production, including devices intended to automate or improve the spinning process. These designs reflect his broader interest in replacing repetitive hand labor with coordinated machinery.
Leonardo did not invent spinning itself. Hand spinning is ancient, and the spinning wheel had already been used in Europe before his lifetime. His proposed machines are better understood as attempts to mechanize stages of an established craft. They show attention to gears, rotation, tension, and the synchronization of moving parts.
A spinning machine should not be confused with a loom. A spinning device makes yarn; a loom interlaces yarns to produce fabric. This distinction matters because Leonardo also studied weaving and other textile mechanisms, but the specific operation in this question is twisting fibres into thread.