Railing re bins at doctor's (8)
I believe the answer is:
banister
'railing' is the definition.
(banister is a kind of railing)
're bins at doctor's' is the wordplay.
'doctor's' indicates an anagram (I've seen 'doctored' mean this).
're'+'bins'+'at'='rebinsat'
'rebinsat' with letters rearranged gives 'BANISTER'.
(Other definitions for banister that I've seen before include "Stair rail" , "Staircase railing" , "Support running alongside stairs" , "Upright supporting handrail of stairs" , "Rail beside a staircase" .)