Dramatically associated with old lace (7)
I believe the answer is:
arsenic
'dramatically associated with old lace' is the definition.
Although both the answer and definition are singular nouns, I don't understand how they can define each other.
This is the entire clue.
Can you help me to learn more?
(Other definitions for arsenic that I've seen before include "Element No 33" , ", it goes with old lace" , "Element with many poisonous compounds" , "Famous stage comedy ''. . . . . . . and Old Lace''" , "Toxic metalloid element" .)