Riddle mostly over hospital for doctors and nurses perhaps? (4)
I believe the answer is:
fish
'doctors and nurses perhaps?' is the definition.
I can't tell whether this definition defines the answer.
'riddle mostly over hospital' is the wordplay.
'riddle' becomes 'sift' (riddle can mean to sieve or sift).
'mostly' means to remove the last letter (most but not all of the word).
'over' says the letters should be written in reverse.
'hospital' becomes 'H' (abbreviation for hospital on maps).
'sift' with its last letter taken off is 'sif'.
'sif' reversed gives 'fis'.
'fis'+'h'='FISH'
'for' is the link.
Can you help me to learn more?
(Other definitions for fish that I've seen before include "Burbot or turbot, for example" , "Aquatic animal(s)" , "counter in various games" , "Swimmer" , "Ruff" .)