She's crazy about India! (4)
I believe the answer is:
maid
'she's' is the definition.
Both the answer and definition are singular nouns.
Maybe there's a link between them I don't understand?
'crazy about india' is the wordplay.
'crazy' becomes 'mad' (synonyms).
'about' indicates putting letters inside.
'india' becomes 'i' (phonetic alphabet: alpha, bravo, charlie etc.).
'mad' placed around 'i' is 'MAID'.
Can you help me to learn more?
(Other definitions for maid that I've seen before include "employee" , "Young woman - servant" , "Damsel" , "Female servant - young girl" , "One in service" .)