If you're talking about the act of spinning yarn:
* Unraveled: This means to undo something that has been spun.
* Untangled: This implies separating something that was spun into a knot or tangle.
* Woven: This is the opposite of spinning in the sense that it refers to creating fabric by interlacing threads.
If you're talking about spinning a story:
* Fact-checked: This refers to verifying the truth of a story.
* Refuted: This means to prove a story false.
* Confirmed: This means to verify that a story is true.
If you're talking about spinning something around:
* Stopped: This means to cease spinning.
* Settled: This means to become still after spinning.
Let me know the context of your question and I can give you a more precise antonym.