Yarn is made of strands of wool twisted together - or spun, as they call it. That's all it means.
However, to spin a yarn means to tell a story.
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The spinning jenny produced yarn faster.
The spinning jenny also made it easier to spin yarn.
It took the place of people who had to spin the yarn.
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Yes at Balacova to spin 'tyre yarn'
Italians (Snia Viscosa?) opened a factory very near to spin
textile yarn.
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Murata vortex spun yarn. It refers to the air vortex technique
used to spin out the fibres when making the yarn. It makes a yarn
which is resistant to pilling.