Messengers very nosey? Nonsense! (6)
I believe the answer is:
envoys
'messengers' is the definition.
(I have seen 'Diplomatic messengers ' mean 'envoys' so perhaps 'messengers' could also mean 'envoys')
'very nosey? nonsense' is the wordplay.
'very' becomes 'v' (abbreviation).
'nonsense' is an anagram indicator.
'v'+'nosey'='vnosey'
'vnosey' anagrammed gives 'ENVOYS'.
(Other definitions for envoys that I've seen before include "Messengers, emissaries" , "Diplomatic messengers" , "Diplomatic emissaries" .)