Star on television demonstrating skincare product (9)
I believe the answer is:
sunscreen
'skincare product' is the definition.
I know nothing about this answer so I can't judge whether this works.
'star on television' is the wordplay.
'star' becomes 'sun' (the Sun is a star).
'on television' becomes 'screen' (I can't justify this - if you can you should give a lot more credence to this answer).
'sun'+'screen'='SUNSCREEN'
'demonstrating' acts as a link.
Can you help me to learn more?
(Other definitions for sunscreen that I've seen before include "UV-blocking lotion" , "Tanning protection" , "protection from harsh light" , "summer holiday preparation" , "Cream" .)