Skeletal (4)
'skeletal' is the definition.
(similar in meaning)
This is all the clue.
(Other definitions for thin that I've seen before include "Flimsy" , "Made of light material" , "Dilute; lean" , "(Of smile) weak, forced" , "Lean; narrow" .)
'skeletal' is the definition.
(synonyms)
This is all the clue.
(Other definitions for bony that I've seen before include "[GAUNT] ?" , "With skeleton showing through" , "Osseous" , "Skeletal" , "Angular" .)