Little girl led by constant ringing (5)
I believe the answer is:
knell
'ringing' is the definition.
(thesaurus)
'little girl led by constant' is the wordplay.
'little girl' becomes 'Nell' (Little Nell, character in The Old Curiosity Shop).
'led by' means one lot of letters go next to another.
'constant' becomes 'k' (I can't justify this - if you can you should believe this answer much more).
'nell' after 'k' is 'KNELL'.
Can you help me to learn more?
(Other definitions for knell that I've seen before include "Solemn warning" , "Temperate" , "''The curfew tolls the ... of parting day'' (Thomas Gray)" , "Sound of tolling bell" , "Funereal bell sound" .)