Award someone extremely overweight (5)
I believe the answer is:
obese
'overweight' is the definition.
(I've seen this before)
'award someone extremely' is the wordplay.
'award' becomes 'OBE' (Order of the British Empire).
'extremely' says to hollow out the word (remove centre letters) (only the extremes of the word are used).
'someone' with its middle removed is 'se'.
'obe'+'se'='OBESE'
(Other definitions for obese that I've seen before include "Unhealthily fat and overweight" , "Enormously portly" , "Extremely portly" , "Very substantial" , "in need of slimming down" .)