It's pretty thin stuff (5)

I believe the answer is:

tulle

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'stuff' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe they are linked in a way I don't understand?

I don't understand the rest of the clue.

Can you help me to learn more?

(Other definitions for tulle that I've seen before include "French town" , "Tutu netting" , "Delicate netted fabric" , "Silk net fabric" , "that may be around one's body" .)

I've seen this clue in the Evening Standard.

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