Change her nappies with no dread (12)
I believe the answer is:
apprehension
'dread' is the definition.
(synonyms)
'change her nappies with no' is the wordplay.
'change' indicates anagramming the letters.
'with' is a charade indicator (letters next to each other).
'her'+'nappies'='hernappies'
'hernappies' after 'no' is 'nohernappies'.
'nohernappies' anagrammed gives 'APPREHENSION'.
(Other definitions for apprehension that I've seen before include "butterflies" , "The catching" , "Trepidation" , "Anxious anticipation; understanding" , "Arrest -- dread" .)