Bombastic trio has Rachel in a spin (10)
I believe the answer is:
rhetorical
'bombastic' is the definition.
(similar in meaning)
'trio has rachel in a spin' is the wordplay.
'has' means one lot of letters go next to another.
'in a spin' is an anagram indicator.
'trio' after 'rachel' is 'racheltrio'.
'racheltrio' with letters rearranged gives 'RHETORICAL'.
(Other definitions for rhetorical that I've seen before include "You don't have to answer this one!" , "in speech" , "using words extravagantly" , "Sort of question" , "manner of speaking" .)