He is let out? Solution - trace! (10)
I believe the answer is:
silhouette
'solution trace' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'he is let out?' is the wordplay.
'he is let out' can be anagrammed to 'SILHOUETTE'.
Though, I am not sure how the anagram is indicated.
Can you help me to learn more?
(Other definitions for silhouette that I've seen before include "Outline representation" , "Profile of characters" , "Outline figure" , "image" , "Shadowy outline" .)