Bill has a little money in a manner of speaking (6)
I believe the answer is:
accent
'manner of speaking' is the definition.
(accent is a kind of manner of speaking)
'bill has a little money' is the wordplay.
'bill' becomes 'ac' (short for account).
'has' means one lot of letters go next to another.
'a little money' becomes 'cent' (coin of little value).
'ac'+'cent'='ACCENT'
'in a' acts as a link.
(Other definitions for accent that I've seen before include "Distinctive way of pronouncing words" , "Acute, perhaps" , "A diacritic mark" , "Distinctive local way of speaking" , "Speech inflection" .)