Detach a line for divers (7)
I believe the answer is:
several
'divers' is the definition.
(thesaurus)
'detach a line' is the wordplay.
'detach' becomes 'sever' (I've seen this before).
'line' becomes 'l'.
'sever'+'a'+'l'='SEVERAL'
'for' acts as a link.
(Other definitions for several that I've seen before include "A good few" , "More than one or two" , "Assorted" , "quite a lot" , "Sundry, distinct" .)