Icy: uncle slipping about — hard to keep one's balance on this (8)
I believe the answer is:
unicycle
'hard to keep one's balance on this' is the definition.
(cycle with only one wheel)
'icy uncle slipping' is the wordplay.
'slipping' indicates anagramming the letters.
'icy'+'uncle'='icyuncle'
'icyuncle' anagrammed gives 'UNICYCLE'.
'about' acts as a link.
(Other definitions for unicycle that I've seen before include "that requires someone well-balanced in control" , "One-wheeled vehicle driven by pedalling" , "Transport needing good balance" , "Means of transport" , "form of transport" .)