Thin, svelte (4)
I believe the answer is:
slim
I believe this clue is a double definition.
'thin' is the first definition.
(I know that thin can be written as slim)
'svelte' is the second definition.
(I know that svelte can be written as slim)
(Other definitions for slim that I've seen before include "Take off weight as by dieting" , "Svelte" , "Bakery produce" , "(Of chance) very slight" , "Slender or slight" .)