Inventor of unintroduced brand fitting in speech (9)
I believe the answer is:
arkwright
'inventor' is the definition.
(I've seen this before)
'unintroduced brand fitting in speech' is the wordplay.
'unintroduced brand' becomes 'ark' (I can't justify this - if you can you should believe this answer much more).
'fitting' becomes 'right' (I've seen this in another clue).
'in speech' shows a homophone (sound like).
'right' sounds like 'wright'.
'ark'+'wright'='ARKWRIGHT'
'of' acts as a link.
Can you help me to learn more?
(Other definitions for arkwright that I've seen before include "Inventor of spinning frame" , "Noah?" , "Spinning machine inventor" , "Who invented a frame?" , "inventive old spinner" .)