Initially a hospital for the sick (at Harrow?) (4)
I believe the answer is:
hill
'harrow?' is the 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?
'initially a hospital for the sick' is the wordplay.
'initially' indicates taking the first letters.
'for' means one lot of letters go next to another.
'the sick' becomes 'ill' (I've seen this before).
The first letter of 'hospital' is 'h'.
'h'+'ill'='HILL'
'at' is the link.
Can you help me to learn more?
(Other definitions for hill that I've seen before include "Miniature mountain" , "Rise" , "Mount" , "Elevation on land" , "High mass of land" .)