Said clearly the aim is to curb the weight (8)
I believe the answer is:
enounced
'said clearly' is the definition.
'enounced' can be an answer for 'said' ('enounce' can be a synonym of 'say'). I'm not certain of the 'clearly' bit.
'the aim is to curb the weight' is the wordplay.
'the aim' becomes 'end' (both can mean a goal or purpose).
'is to curb' is an insertion indicator (curb can mean to restrain or contain).
'the weight' becomes 'ounce' (ounce is a kind of weight).
'end' placed around 'ounce' is 'ENOUNCED'.
Can you help me to learn more?
(Another definition for enounced that I've seen is " spoke with great precision".)