Material that's light when worn (5)

I believe the answer is:

rayon

I'm a little stuck... Click here to teach me more about this clue!

'material' is the definition.
(rayon is a type of fabric)

'light when worn' is the wordplay.
'light when' becomes 'ray' (ray is a kind of light. I am not sure about the 'when' bit.).
'worn' becomes 'on' (as in having clothes on).
'ray'+'on'='RAYON'

'that's' is the link.

Can you help me to learn more?

(Other definitions for rayon that I've seen before include "Synthetic material" , "No ray (anag)" , "Or any (anag) -- fibre" , "Cellulose fabric" , "Artificial fibre" .)

I've seen this clue in The Globe and Mail.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.