The little chap's in hospital (5)
I believe the answer is:
barts
'hospital' is the definition.
(I've seen this before)
'the little chap's' is the wordplay.
I cannot quite understand how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is found in the answer.
'chap's' could be 'bars' and 'bars' is found within the remaining letters.
No letters remain.
This may be the basis of clue (or it may be nonsense).
'in' is the link.
Can you help me to learn more?
(Another definition for barts that I've seen is " hospital".)