What is the collective nouns of thread?

There isn't a specific, widely accepted collective noun for thread. However, you could use some descriptive phrases depending on the context:

For a group of threads bundled together:

* A skein of thread

* A spool of thread

* A ball of thread

* A hank of thread

* A bundle of thread

* A coil of thread

For threads in a particular context:

* A tapestry of threads (for threads woven together)

* A web of threads (for threads forming a network)

* A tangle of threads (for threads that are knotted or tangled)

Ultimately, the best collective noun will depend on the specific situation and the desired effect.