Stuck (to) (7)
I believe the answer is:
adhered
'stuck to' is the definition.
('adhere' can be a synonym of 'stick to')
This is the entire clue.
(Other definitions for adhered that I've seen before include "Stuck; glued" , "Stuck (to something)" , "Stuck - redhead (anag)" , "Stuck to, remained loyal" , "Showed sticking power" .)