Play on words at the outset piquing global body (3)
I believe the answer is:
pun
'play on words' is the definition.
(synonyms)
'at the outset piquing global body' is the wordplay.
'at the outset' suggests taking the first letters (the outset is the beginning).
'global body' becomes 'UN' (United Nations).
The initial letter of 'piquing' is 'p'.
'p'+'un'='PUN'
(Other definitions for pun that I've seen before include "A play on words, perhaps the lowest form of wit" , "Double entendre" , "conceit by a wordsmith?" , "Bit of paronomasia; witticism" , "joke" .)