Nothing perceptible initially, standing in shadow (10)
I believe the answer is:
opposition
'shadow' is the definition.
The answer and definition can be both people as well as being singular nouns.
Perhaps there's an association between them I don't understand?
'nothing perceptible initially standing' is the wordplay.
'nothing' becomes 'O' (looks like zero - 0).
'initially' indicates taking the first letters.
'standing' becomes 'position' (I can't explain this - if you can you should give a lot more credence to this answer).
The first letter of 'perceptible' is 'p'.
'o'+'p'+'position'='OPPOSITION'
'in' is the link.
Can you help me to learn more?
(Other definitions for opposition that I've seen before include "organized political group" , "those out of power" , "antagonism" , "Rivalry" , "Resistance, dissent" .)