New net cord starts tight (9)
I believe the answer is:
stringent
'tight' is the definition.
(synonyms)
'new net cord starts' is the wordplay.
'new' indicates an anagram.
'cord' becomes 'string' (string is a kind of cord).
'starts' is a charade indicator (letters next to each other).
'net' with letters rearranged gives 'ent'.
'ent' after 'string' is 'STRINGENT'.
(Other definitions for stringent that I've seen before include "tightly drawn" , "Strict, rigorous" , "Uncompromising" , "Harsh" , "Tight" .)