Language used in baffling organisers (5)
I believe the answer is:
lingo
'language' is the definition.
(informal term for language)
'in baffling organisers' is the wordplay.
'in' indicates a hidden word.
'LINGO' is hidden in the letters of 'baffling organisers'.
'used' acts as a link.
(Other definitions for lingo that I've seen before include "Johnny Foreigner speaks one" , "Vernacular" , "Language (slang)" , "Language (informally)" , "strange language" .)