Try silver dresses in a state of excitement (4)
I believe the answer is:
agog
'in a state of excitement' is the definition.
(I've seen this in another clue)
'try silver dresses' is the wordplay.
'try' becomes 'go' (both can mean an attempt).
'silver' becomes 'Ag' (Ag is the chemical symbol for silver).
'dresses' means one lot of letters goes inside another (dress can mean cover).
'go' going within 'ag' is 'AGOG'.
(Other definitions for agog that I've seen before include "All ears" , "Excitedly interested" , "Eager and wide-eyed" , "Interested, excited and eager to know more" , "Excitedly eager" .)