Ingredient in silver works shortly (4)
I believe the answer is:
agar
'ingredient in' is the definition.
The answer and definition can be both substances as well as being singular nouns.
Maybe you can see an association between them that I don't see?
'silver works shortly' is the wordplay.
'silver' becomes 'Ag' (Ag is the chemical symbol for silver).
'works' becomes 'art' (I've seen this before).
'shortly' means to remove the last letter.
'art' with its last letter taken off is 'ar'.
'ag'+'ar'='AGAR'
Can you help me to learn more?
(Other definitions for agar that I've seen before include "Medium for growth" , "Seaweed jelly" , "part of culture?" , "found in the sea" , "Jelly used in bacteria culture" .)