This provides some understanding for one who moves on the ice (7)
I believe the answer is:
slipper
This could be a double definition.
'this provides some understanding for one' is the first definition.
The definition suggests a singular noun which matches the answer.
'moves on the ice' is the second definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe there's a link between them I don't understand?
'who' is the link.
Can you help me to learn more?
(Other definitions for slipper that I've seen before include "Nearby; pub" , "Comfortable shoe" , "One losing footing" , "Footwear item" , "Casual footwear" .)