PM pleased with weight (9)
I believe the answer is:
gladstone
'pm' is the definition.
(Victorian UK prime minister William Gladstone)
'pleased with weight' is the wordplay.
'pleased' becomes 'glad' (similar in meaning).
'with' says to put letters next to each other.
'weight' becomes 'stone' (stone is a kind of weight).
'glad'+'stone'='GLADSTONE'
(Other definitions for gladstone that I've seen before include "Victorian PM" , "Bag for a former British statesman" , "5,27 [PRIME MINISTER]" , "Victorian GOM" , "Former British prime minister and large travelling bag" .)