Cheap cheese initially appetising: puts more out (9)
I believe the answer is:
mousetrap
'cheap cheese' is the definition.
(I've seen this before)
'initially appetising puts more out' is the wordplay.
'initially' says to take the initial letters.
'out' indicates anagramming the letters (out can mean wrong or inaccurate).
The first letter of 'appetising' is 'a'.
'a'+'puts'+'more'='aputsmore'
'aputsmore' is an anagram of 'MOUSETRAP'.
(Other definitions for mousetrap that I've seen before include "Poor (cheese); route maps (anag.)" , "Rodent catcher" , "Snare for vermin" , "Cheese-baited snare" , "Poor cheese (colloq.)" .)