Relative from Zurich for example, oddly? (3)
I believe the answer is:
sis
'relative' is the definition.
(short for sister)
I can't explain the rest of the clue.
(Other definitions for sis that I've seen before include "Girl" , "Secret Intelligence Service (abbr.)" , "Secret Intelligence Service (abbreviation)" , "relative" , "Sibling (informal)" .)