Insignificant two-dimensional character (6,5)
I believe the answer is:
mickey mouse
This could be a double definition.
'insignificant' is the first definition.
(I've seen this before)
'two-dimensional character' is the second definition.
'mickey mouse' can be an answer for 'character' (I've seen this before). I am unsure of the 'two-dimensional' bit.
Can you help me to learn more?
(Other definitions for mickey mouse that I've seen before include "Disney character" , "Walt Disney creation" , "Character that's animated" , "Useless" , "two-dimensional creation" .)