Collection of threads, of a sort Crossword Clue

 The answer to the crossword clue "collection of threads, of a sort" is GARMENT. A garment is a piece of clothing, and it is made up of many threads. So, a collection of threads could be considered a garment, of a sort.

Here are some other words that could fit the crossword clue:

Raiment

Dress

Clothing

Fabric

Textile

Thread

I hope this helps! Let me know if you have any other questions.