Miss little monster having sliced off head (5)
I believe the answer is:
error
'sliced off head' is the definition.
The definition and answer can be both acts as well as being singular nouns.
Perhaps there's a link between them I don't understand?
'miss little monster' is the wordplay.
'miss' becomes 'err' (I've seen this in another clue).
'little' means to remove the last letter (the word is not quite complete).
'monster' becomes 'orc' (fantasy creature).
'orc' with its final letter removed is 'or'.
'err'+'or'='ERROR'
'having' is the link.
Can you help me to learn more?
(Other definitions for error that I've seen before include "Slip, mistake" , "Gaffe" , "Slip-up" , "Faulty judgement" , "1 down" .)