Huge chaps in semi relocating (7)
I believe the answer is:
immense
'huge' is the definition.
(I know that huge can be written as immense)
'chaps in semi relocating' is the wordplay.
'chaps' becomes 'men' (chap can mean a man).
'in' means one lot of letters goes inside another.
'relocating' is an anagram indicator (I've seen 'relocated' mean this).
'semi' anagrammed gives 'imse'.
'men' inserted within 'imse' is 'IMMENSE'.
(Other definitions for immense that I've seen before include "Jumbo" , "Unusually large or great" , "'Gigantic, extensive (7)'" , "Superb" , "Huge, considerable" .)