Embrace - the conclusion is big (4)
I believe the answer is:
huge
'is big' is the definition.
(similar in meaning)
'embrace the conclusion' is the wordplay.
'embrace' becomes 'hug' (hug is a kind of embrace).
'conclusion' says to take the final letters.
The last letter of 'the' is 'e'.
'hug'+'e'='HUGE'
(Other definitions for huge that I've seen before include "Enormous" , "Massive" , "Mammoth" , "Colossal" , "Jumbo" .)