Figure it as a mark on one's head (5)
I believe the answer is:
oscar
'figure it' is the definition.
I can't judge whether this defines the answer.
'a mark on one's head' is the wordplay.
'a mark' becomes 'scar' (mark left by an injury).
'on' says to put letters next to each other.
'head' says to take the initial letters.
The first letter of 'ones' is 'o'.
'scar' put after 'o' is 'OSCAR'.
'as' is the link.
Can you help me to learn more?
(Other definitions for oscar that I've seen before include "Wildean film award?" , "- - Peterson, pianist" , "Film prize" , "Film-prize statuette" , "The familiar Mr Wilde, playwright" .)