Small ignoramus I brought before head for indecency (10)
I believe the answer is:
smuttiness
'indecency' is the definition.
(smuttiness is a kind of indecency)
'small ignoramus i brought before head' is the wordplay.
I cannot really understand how this works, but
'small' could be 'sm' and 'sm' is located in the answer.
'i' is present in the answer.
'before' could be 'e' (I've seen this in other clues) and 'e' is located in the answer.
This explanation may well be incorrect...
'for' is the link.
Can you help me to learn more?
(Another definition for smuttiness that I've seen is " Mild indecency".)