Street is a great distance from hospital for one going on foot (8)
I believe the answer is:
wayfarer
'street' is the definition.
Although both the answer and definition are singular nouns, I cannot see how one could define the other.
'great distance from hospital for one going on foot' is the wordplay.
I cannot quite see how this works, but
'distance' could be 'way' (way is a kind of distance) and 'way' is found in the answer.
'one' could be 'a' and 'a' is located in the answer.
'on' could be 're' ('on' can be mean 'with reference to') and 're' is found within the answer.
'foot' could be 'f' (abbreviation) and 'f' is found within the answer.
A single letter 'r' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
'is a' is the link.
Can you help me to learn more?
(Other definitions for wayfarer that I've seen before include "Person on a journey - sailing dinghy" , "One walking" , "Person who travels on foot" , "Traveller, especially on foot" , "Trekker" .)