Emma's possibly greeting British lady in India (8)
I believe the answer is:
'lady in india' is the definition.
The definition and answer can be both people as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'emma's possibly greeting british' is the wordplay.
'possibly' indicates an anagram.
'greeting' becomes 'hi' (hi is a kind of greeting).
'british' becomes 'b' (abbreviation e.g. in 'BBC').
'emmas' is an anagram of 'memsa'.
Can you help me to learn more?
(Other definitions for memsahib that I've seen before include "Old Indian term for European married woman" , "Polite form of address for a woman in India" , "Raj lady's address" , "Indian madam" , "In colonial India, term of respect used of a married European woman" .)