New game not given a lot of weight (7)
I believe the answer is:
megaton
'weight' is the definition.
(megaton is a kind of weight)
'new game not given' is the wordplay.
'new' indicates an anagram.
'given' means one lot of letters go next to another.
'game' put after 'not' is 'notgame'.
'notgame' with letters rearranged gives 'MEGATON'.
'a lot of' is the link.
This may not be right. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for megaton that I've seen before include "Explosive power equivalent to one million tons of TNT" , "weight" , "Powerful explosive unit" , "it weighs a lot" , "Measure of explosive power - montage (anag)" .)