Big woman here in matrimonial crime? Little woman! (3)
I believe the answer is:
amy
This clue could be a double definition.
'big woman here in matrimonial crime?' is the first definition.
The definition suggests a singular noun which matches the answer.
'little woman' is the second definition.
(character from the novel Little Women)
Can you help me to learn more?
(Other definitions for amy that I've seen before include "-- Winehouse, singer" , "so-called little woman" , "Youngest of Little Women" , "Girl" , "- Johnson, Eng. aviator" .)