Gambler taking odds with a spot (9)
I believe the answer is:
bespatter
'spot' is the definition.
(I know that bespatter is a more specific form of the action spot)
'gambler taking odds with a' is the wordplay.
'gambler' becomes 'better' (someone who makes bets is a gambler).
'taking' indicates putting letters inside.
'odds' becomes 'sp' (betting abbreviation for starting price).
'with' means one lot of letters go next to another.
'sp'+'a'='spa'
'better' placed around 'spa' is 'BESPATTER'.
(Other definitions for bespatter that I've seen before include "Dirty" , "Defame" , "Make mess of" , "Spray with droplets" .)