Kingsley or Martin (4)
I believe the answer is:
amis
'kingsley or martin' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for amis that I've seen before include "Kingsley, Martin or John" , "Author of Lucky Jim, d.1995" , "Martin --, Eng. author" , "English writer" , "Kingsley -, English author (Lucky Jim)" .)