Format of cartoon is to take off (5)
I believe the answer is:
strip
This clue might be a double definition.
'format of cartoon' is the first definition.
'strip' can be an answer for 'cartoon' (strip is a kind of cartoon). I am not certain of the 'format of' bit.
'is to take off' is the second definition.
(I've seen this in another clue)
Can you help me to learn more?
(Other definitions for strip that I've seen before include "Tear off" , "Remove clothes - maybe comic" , "Thin piece" , "Team kit" , "Series of cartoons" .)