County on the Strait of Dover (4)
I believe the answer is:
kent
'county on the strait of dover' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for kent that I've seen before include "Garden of England - Superman's family name" , "known to Scots" , "County, garden of England" , "Part of 1 25 [KING LEAR]" , "County; punting pole" .)