Supplied about nine on a regular basis (5)
I believe the answer is:
fixed
'supplied about nine on a regular basis' is the definition.
I can't judge whether this defines the answer.
'supplied about nine' is the wordplay.
'supplied' becomes 'fed' (feeding is a kind of supplying).
'about' means one lot of letters goes inside another.
'nine' becomes 'IX' (roman numeral).
'fed' placed around 'ix' is 'FIXED'.
Can you help me to learn more?
(Other definitions for fixed that I've seen before include "Set" , "Arranged" , "Established" , "Repaired" , "Securely fastened" .)