It could suggest I step where one may slither dangerously? (3-5)

I believe the answer is:

off-piste

'where one may slither dangerously?' is the definition.
(as in skiing off-piste, away from prepared ski run)

I cannot understand how the rest of the clue works.

(Other definitions for off-piste that I've seen before include "Away from the regular runs in skiing" , "On unauthorised ski slope" , "Away from prepared ski runs" .)

I've seen this clue in The Times.

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