Meaningless hearing, six implicated (7)
I believe the answer is:
trivial
'meaningless' is the definition.
(thesaurus)
'hearing six implicated' is the wordplay.
I cannot quite see how this works, but
'six' could be 'vi' ('vi' can be a synonym of 'six') and 'vi' is found in the answer.
'hearing' could be 'trial' (I've seen this before) and 'trial' is present in the leftover letters.
This accounts for all the letters.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for trivial that I've seen before include "Frivolous" , "Meaningless" , "Worthless" , "Popular board game" , "Rival it, being unimportant" .)