Eccentric adult duck occasionally interrupting plan (6)
I believe the answer is:
madcap
'eccentric' is the definition.
The definition and answer can be both people as well as being singular nouns.
Maybe you can see a link between them that I can't see?
'adult duck occasionally interrupting plan' is the wordplay.
'adult' becomes 'a'.
'occasionally' indicates alternate letters.
'interrupting' indicates putting letters inside.
'plan' becomes 'map' (I've seen this before**).
The alternate letters of 'duck' are 'dc'.
'a'+'dc'='adc'
'adc' put within 'map' is 'MADCAP'.
Can you help me to learn more?
(Other definitions for madcap that I've seen before include "Foolhardy" , "Silly" , "Impetuous irresponsible person" , "Reckless girl" , "Foolish, reckless" .)