I step out on the slope (5)
I believe the answer is:
piste
'the slope' is the definition.
(I have seen 'slippery slope' mean 'piste' so perhaps 'slope' could also mean 'piste')
'i step out on' is the wordplay.
'out' is an anagram indicator (out can mean wrong or inaccurate).
'on' is an insertion indicator (as in clothing 'on' a person).
'step' with letters rearranged gives 'pste'.
'i' placed inside 'pste' is 'PISTE'.
(Other definitions for piste that I've seen before include "Ski-slope" , "Ski slope" , "slippery slope" , "Ski trail" , "strip of fencing" .)