Doctor lost in Georgia area becomes homesick (9)

I believe the answer is:

nostalgia

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But I can't explain it at all! Could you help me understand?

(Other definitions for nostalgia that I've seen before include "Looking back with fondness on the past" , "Attraction to the past" , "A longing for past times" , "Longing for something past - isn't a goal (anag)" , "Wistful remembrance of analogist" .)

I've seen this clue in The Hindu.

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