Step surface (5)
I believe the answer is:
tread
(Other definitions for tread that I've seen before include "between the car and the road" , "March" , "A measurement of tyre" , "Gripping part of tyre" , "Part of flight" .)
I believe the answer is:
tread
(Other definitions for tread that I've seen before include "between the car and the road" , "March" , "A measurement of tyre" , "Gripping part of tyre" , "Part of flight" .)