Tiny trace maybe but you can bet on it (9)
I believe the answer is:
certainty
'you can bet on it' is the definition.
I can't tell whether this definition defines the answer.
'tiny trace maybe' is the wordplay.
'maybe' indicates an anagram.
'tiny'+'trace'='tinytrace'
'tinytrace' with letters rearranged gives 'CERTAINTY'.
'but' acts as a link.
Can you help me to learn more?
(Other definitions for certainty that I've seen before include "Sureness" , "Banker" , "Foregone conclusion" , "Conviction" , "It's inevitable" .)